feat: thunar & papirus-folders theming + new schemes (#80)

* feat: GTK app theming system

- Implemented custom.css import for user-managed app themes
- process_app_themes() to dynamically update colors in imported CSS files
- Inline comment markers for color replacement (e.g, /* accent-color */)
- Papirus icon color syncing with weighted hue/saturation algorithm

This allows users to create modular app themes that automatically update when the scheme/wallpaper changes

Example usage:
  .app .element { color: #24BD5C; /* accent-color */ }
  .app .element:hover { background: rgba(36, 189, 92, 0.15); /* accent-color with 15% opacity */ }

* feat: atomic theme changes with locking and mode-specific CSS

- Implemented locking to prevent concurrent theme changes
- Added mode-light/mode-dark CSS markers for dynamic property reordering
- Made terminal writes and Papirus sync non-blocking to prevent hangs
- Only save scheme.json after successful theme application

Fixes race conditions during rapid theme switching and ensures Shell and GTK apps scheme stay in sync.

* theme: added to color mapping for custom theming, new schemes

* theme: quick fixes, cleanup

* theme: include thunar.css as template, with new theming system

* theme: modified GTK theming approach

- Dropped comment targeted theming in favor for existing {{  }} replacement
- [app].css.template file created for customization, bypassing built in default if present
- Handling *.template for added templates to be parsed and added to import

* theme: fixes for  thunar.css

* theme: remove .template file use

* theme: path button color adjustment, non-active hover

* fixes & cleanup

* thunar css fixes

* more css fixes

* format

* fix tab vert spacing

---------

Co-authored-by: 2 * r + 2 * t <61896496+soramanew@users.noreply.github.com>

src/caelestia/data/schemes/everforest/hard/dark.txt

@@ -0,0 +1,110 @@
+primary_paletteKeyColor 7FBBB3
+secondary_paletteKeyColor 83C092
+tertiary_paletteKeyColor A7C080
+neutral_paletteKeyColor 2E383C
+neutral_variant_paletteKeyColor 374145
+background 1E2326
+onBackground D3C6AA
+surface 252B2E
+surfaceDim 15191C
+surfaceBright 343E43
+surfaceContainerLowest 11161A
+surfaceContainerLow 2A3338
+surfaceContainer 2E383C
+surfaceContainerHigh 343E43
+surfaceContainerHighest 3A4448
+onSurface D3C6AA
+surfaceVariant 374145
+onSurfaceVariant 9DA9A0
+inverseSurface D3C6AA
+inverseOnSurface 1E2326
+outline 859289
+outlineVariant 414B50
+shadow 000000
+scrim 000000
+surfaceTint 7FBBB3
+primary 7FBBB3
+onPrimary 1E2326
+primaryContainer 414B50
+onPrimaryContainer A7C080
+inversePrimary 5A9A8F
+secondary 83C092
+onSecondary 1E2326
+secondaryContainer 414B50
+onSecondaryContainer A7C080
+tertiary A7C080
+onTertiary 1E2326
+tertiaryContainer 414B50
+onTertiaryContainer D3C6AA
+error E67E80
+onError 1E2326
+errorContainer 4C3743
+onErrorContainer E67E80
+primaryFixed 7FBBB3
+primaryFixedDim 5A9A8F
+onPrimaryFixed 1E2326
+onPrimaryFixedVariant 374145
+secondaryFixed 83C092
+secondaryFixedDim 5F8C6F
+onSecondaryFixed 1E2326
+onSecondaryFixedVariant 374145
+tertiaryFixed A7C080
+tertiaryFixedDim 7F9D5F
+onTertiaryFixed 1E2326
+onTertiaryFixedVariant 374145
+term0 1E2326
+term1 E67E80
+term2 A7C080
+term3 DBBC7F
+term4 7FBBB3
+term5 D699B6
+term6 83C092
+term7 D3C6AA
+term8 859289
+term9 E67E80
+term10 A7C080
+term11 DBBC7F
+term12 7FBBB3
+term13 D699B6
+term14 83C092
+term15 D3C6AA
+rosewater D3C6AA
+flamingo D699B6
+pink D699B6
+mauve D699B6
+red E67E80
+maroon E67E80
+peach E69875
+yellow DBBC7F
+green A7C080
+teal 83C092
+sky 7FBBB3
+sapphire 7FBBB3
+blue 7FBBB3
+lavender 7FBBB3
+klink 7FBBB3
+klinkSelection 7FBBB3
+kvisited 83C092
+kvisitedSelection 83C092
+knegative E67E80
+knegativeSelection E67E80
+kneutral DBBC7F
+kneutralSelection DBBC7F
+kpositive A7C080
+kpositiveSelection A7C080
+text D3C6AA
+subtext1 9DA9A0
+subtext0 859289
+overlay2 7A8478
+overlay1 6F7A6F
+overlay0 5F6A5F
+surface2 2E383C
+surface1 252B2E
+surface0 1E2326
+base 1E2326
+mantle 15191C
+crust 11161A
+success A7C080
+onSuccess 1E2326
+successContainer 414B50
+onSuccessContainer D3C6AA

src/caelestia/data/schemes/everforest/medium/dark.txt

@@ -0,0 +1,110 @@
+primary_paletteKeyColor 7FBBB3
+secondary_paletteKeyColor 83C092
+tertiary_paletteKeyColor A7C080
+neutral_paletteKeyColor 2E383C
+neutral_variant_paletteKeyColor 374145
+background 2D353B
+onBackground D3C6AA
+surface 343F44
+surfaceDim 232A2E
+surfaceBright 475258
+surfaceContainerLowest 1E2326
+surfaceContainerLow 3B474E
+surfaceContainer 3D484D
+surfaceContainerHigh 475258
+surfaceContainerHighest 4C5258
+onSurface D3C6AA
+surfaceVariant 3D484D
+onSurfaceVariant 9DA9A0
+inverseSurface D3C6AA
+inverseOnSurface 2D353B
+outline 859289
+outlineVariant 475258
+shadow 000000
+scrim 000000
+surfaceTint 7FBBB3
+primary 7FBBB3
+onPrimary 2D353B
+primaryContainer 475258
+onPrimaryContainer A7C080
+inversePrimary 5A9A8F
+secondary 83C092
+onSecondary 2D353B
+secondaryContainer 475258
+onSecondaryContainer A7C080
+tertiary A7C080
+onTertiary 2D353B
+tertiaryContainer 475258
+onTertiaryContainer D3C6AA
+error E67E80
+onError 2D353B
+errorContainer 4C3743
+onErrorContainer E67E80
+primaryFixed 7FBBB3
+primaryFixedDim 5A9A8F
+onPrimaryFixed 2D353B
+onPrimaryFixedVariant 374145
+secondaryFixed 83C092
+secondaryFixedDim 5F8C6F
+onSecondaryFixed 2D353B
+onSecondaryFixedVariant 374145
+tertiaryFixed A7C080
+tertiaryFixedDim 7F9D5F
+onTertiaryFixed 2D353B
+onTertiaryFixedVariant 374145
+term0 2D353B
+term1 E67E80
+term2 A7C080
+term3 DBBC7F
+term4 7FBBB3
+term5 D699B6
+term6 83C092
+term7 D3C6AA
+term8 859289
+term9 E67E80
+term10 A7C080
+term11 DBBC7F
+term12 7FBBB3
+term13 D699B6
+term14 83C092
+term15 D3C6AA
+rosewater D3C6AA
+flamingo D699B6
+pink D699B6
+mauve D699B6
+red E67E80
+maroon E67E80
+peach E69875
+yellow DBBC7F
+green A7C080
+teal 83C092
+sky 7FBBB3
+sapphire 7FBBB3
+blue 7FBBB3
+lavender 7FBBB3
+klink 7FBBB3
+klinkSelection 7FBBB3
+kvisited 83C092
+kvisitedSelection 83C092
+knegative E67E80
+knegativeSelection E67E80
+kneutral DBBC7F
+kneutralSelection DBBC7F
+kpositive A7C080
+kpositiveSelection A7C080
+text D3C6AA
+subtext1 9DA9A0
+subtext0 859289
+overlay2 7A8478
+overlay1 6F7A6F
+overlay0 5F6A5F
+surface2 3D484D
+surface1 343F44
+surface0 2D353B
+base 2D353B
+mantle 232A2E
+crust 1E2326
+success A7C080
+onSuccess 2D353B
+successContainer 475258
+onSuccessContainer D3C6AA

src/caelestia/data/schemes/everforest/medium/light.txt

@@ -0,0 +1,110 @@
+primary_paletteKeyColor 3A94C5
+secondary_paletteKeyColor 35A77C
+tertiary_paletteKeyColor 8DA101
+neutral_paletteKeyColor E6E2CC
+neutral_variant_paletteKeyColor E0DCC7
+background FDF6E3
+onBackground 5C6A72
+surface F3EAD3
+surfaceDim FDF6E3
+surfaceBright FFFBF0
+surfaceContainerLowest FFFBF0
+surfaceContainerLow FDF6E3
+surfaceContainer F3EAD3
+surfaceContainerHigh EAE4CA
+surfaceContainerHighest E0DCC7
+onSurface 5C6A72
+surfaceVariant EAE4CA
+onSurfaceVariant 6F7C84
+inverseSurface 5C6A72
+inverseOnSurface FDF6E3
+outline 939F91
+outlineVariant E0DCC7
+shadow 000000
+scrim 000000
+surfaceTint 3A94C5
+primary 3A94C5
+onPrimary FFFBF0
+primaryContainer E0DCC7
+onPrimaryContainer 8DA101
+inversePrimary 5FAFD7
+secondary 35A77C
+onSecondary FFFBF0
+secondaryContainer E0DCC7
+onSecondaryContainer 8DA101
+tertiary 8DA101
+onTertiary FFFBF0
+tertiaryContainer E0DCC7
+onTertiaryContainer 5C6A72
+error F85552
+onError FFFBF0
+errorContainer E6E2CC
+onErrorContainer F85552
+primaryFixed 3A94C5
+primaryFixedDim 5FAFD7
+onPrimaryFixed FFFBF0
+onPrimaryFixedVariant E0DCC7
+secondaryFixed 35A77C
+secondaryFixedDim 5FC198
+onSecondaryFixed FFFBF0
+onSecondaryFixedVariant E0DCC7
+tertiaryFixed 8DA101
+tertiaryFixedDim A7C080
+onTertiaryFixed FFFBF0
+onTertiaryFixedVariant E0DCC7
+term0 5C6A72
+term1 F85552
+term2 8DA101
+term3 DFA000
+term4 3A94C5
+term5 DF69BA
+term6 35A77C
+term7 5C6A72
+term8 939F91
+term9 F85552
+term10 8DA101
+term11 DFA000
+term12 3A94C5
+term13 DF69BA
+term14 35A77C
+term15 5C6A72
+rosewater 5C6A72
+flamingo DF69BA
+pink DF69BA
+mauve DF69BA
+red F85552
+maroon F85552
+peach E66868
+yellow DFA000
+green 8DA101
+teal 35A77C
+sky 3A94C5
+sapphire 3A94C5
+blue 3A94C5
+lavender 3A94C5
+klink 3A94C5
+klinkSelection 3A94C5
+kvisited 35A77C
+kvisitedSelection 35A77C
+knegative F85552
+knegativeSelection F85552
+kneutral DFA000
+kneutralSelection DFA000
+kpositive 8DA101
+kpositiveSelection 8DA101
+text 5C6A72
+subtext1 6F7C84
+subtext0 939F91
+overlay2 A6B0A0
+overlay1 B9C0B0
+overlay0 CCD3C2
+surface2 EAE4CA
+surface1 F3EAD3
+surface0 FDF6E3
+base FDF6E3
+mantle FFFBF0
+crust FFFEF9
+success 8DA101
+onSuccess FFFBF0
+successContainer E0DCC7
+onSuccessContainer 5C6A72

src/caelestia/data/schemes/everforest/soft/dark.txt

@@ -0,0 +1,110 @@
+primary_paletteKeyColor 7FBBB3
+secondary_paletteKeyColor 83C092
+tertiary_paletteKeyColor A7C080
+neutral_paletteKeyColor 2E383C
+neutral_variant_paletteKeyColor 374145
+background 323C41
+onBackground D3C6AA
+surface 3A454A
+surfaceDim 282F34
+surfaceBright 4D585D
+surfaceContainerLowest 232A2E
+surfaceContainerLow 414D54
+surfaceContainer 434E53
+surfaceContainerHigh 4D585D
+surfaceContainerHighest 525C61
+onSurface D3C6AA
+surfaceVariant 434E53
+onSurfaceVariant 9DA9A0
+inverseSurface D3C6AA
+inverseOnSurface 323C41
+outline 859289
+outlineVariant 4D585D
+shadow 000000
+scrim 000000
+surfaceTint 7FBBB3
+primary 7FBBB3
+onPrimary 323C41
+primaryContainer 4D585D
+onPrimaryContainer A7C080
+inversePrimary 5A9A8F
+secondary 83C092
+onSecondary 323C41
+secondaryContainer 4D585D
+onSecondaryContainer A7C080
+tertiary A7C080
+onTertiary 323C41
+tertiaryContainer 4D585D
+onTertiaryContainer D3C6AA
+error E67E80
+onError 323C41
+errorContainer 4C3743
+onErrorContainer E67E80
+primaryFixed 7FBBB3
+primaryFixedDim 5A9A8F
+onPrimaryFixed 323C41
+onPrimaryFixedVariant 374145
+secondaryFixed 83C092
+secondaryFixedDim 5F8C6F
+onSecondaryFixed 323C41
+onSecondaryFixedVariant 374145
+tertiaryFixed A7C080
+tertiaryFixedDim 7F9D5F
+onTertiaryFixed 323C41
+onTertiaryFixedVariant 374145
+term0 323C41
+term1 E67E80
+term2 A7C080
+term3 DBBC7F
+term4 7FBBB3
+term5 D699B6
+term6 83C092
+term7 D3C6AA
+term8 859289
+term9 E67E80
+term10 A7C080
+term11 DBBC7F
+term12 7FBBB3
+term13 D699B6
+term14 83C092
+term15 D3C6AA
+rosewater D3C6AA
+flamingo D699B6
+pink D699B6
+mauve D699B6
+red E67E80
+maroon E67E80
+peach E69875
+yellow DBBC7F
+green A7C080
+teal 83C092
+sky 7FBBB3
+sapphire 7FBBB3
+blue 7FBBB3
+lavender 7FBBB3
+klink 7FBBB3
+klinkSelection 7FBBB3
+kvisited 83C092
+kvisitedSelection 83C092
+knegative E67E80
+knegativeSelection E67E80
+kneutral DBBC7F
+kneutralSelection DBBC7F
+kpositive A7C080
+kpositiveSelection A7C080
+text D3C6AA
+subtext1 9DA9A0
+subtext0 859289
+overlay2 7A8478
+overlay1 6F7A6F
+overlay0 5F6A5F
+surface2 434E53
+surface1 3A454A
+surface0 323C41
+base 323C41
+mantle 282F34
+crust 232A2E
+success A7C080
+onSuccess 323C41
+successContainer 4D585D
+onSuccessContainer D3C6AA