feat: initial fish shell configuration

- Core config layered on CachyOS base with Catppuccin Mocha theming
- Fisher plugins: fzf.fish, catppuccin, autopair, replay, puffer-fish, magic-enter, spark
- Smart CLI wrappers with fallbacks (bat, lsd, btop, dust, prettyping)
- Custom functions: git, docker, network, kitty, AI session management
- Extensive abbreviation system for keyboard-driven workflows
- Secrets/local sourcing pattern for private and machine-specific config
- README with full documentation and personalization guide
- AGPLv3+ license with copyright headers on all source files

functions/_autopair_insert_left.fish

@@ -0,0 +1,13 @@
+function _autopair_insert_left --argument-names left right
+    set --local buffer (commandline)
+    set --local before (commandline --cut-at-cursor)
+
+    commandline --insert -- $left
+
+    switch "$buffer"
+        case "$before"{," "\*,$autopair_right\*}
+            set --local index (commandline --cursor)
+            commandline --insert -- $right
+            commandline --cursor $index
+    end
+end