docs: clarify that plugin functionality is bundled, not managed by fisher

Only jorgebucaran/fisher itself is in fish_plugins. The functionality
from catppuccin/fish, fzf.fish, done, autopair, and puffer-fish is
bundled directly with this config in modified form and must not be
installed or updated via fisher.

Removes sponge (not present), corrects file path mappings for bundled
components, fixes stale "Plugin sync failed" message in first_run.fish,
and expands fish-config.index with missing sections 9–11.

docs/fish-config.index

@@ -29,8 +29,8 @@ keybindings=# 3. KEY BINDINGS
 bindings=# 3. KEY BINDINGS
 key-bindings=# 3. KEY BINDINGS
 keys=# 3. KEY BINDINGS
-fzf-bindings=## FZF Bindings (from fzf --fish integration)
-fzf=## FZF Bindings (from fzf --fish integration)
+fzf-bindings=## FZF Bindings (bundled from PatrickF1/fzf.fish)
+fzf=## FZF Bindings (bundled from PatrickF1/fzf.fish)
 
 # ── Section 4: Abbreviations ──────────────────────────────────
 abbreviations=# 4. ABBREVIATIONS
@@ -166,10 +166,24 @@ universal=## Fish Universal Variables
 # ── Section 8: Fisher Plugins ─────────────────────────────────
 plugins=# 8. FISHER PLUGINS
 fisher=# 8. FISHER PLUGINS
+bundled-plugins=## Bundled Plugin Functionality
+fish-plugins-manifest=## fish_plugins Manifest
 
-# ── Section 9: Viewing This Manual ───────────────────────────
-viewing=# 9. VIEWING THIS MANUAL
-manual=# 9. VIEWING THIS MANUAL
+# ── Section 9: Installation ────────────────────────────────────
+installation=# 9. INSTALLATION
+install=# 9. INSTALLATION
+sentinel=## Return Sentinel
+updating=## Updating
+
+# ── Section 10: Personalization ───────────────────────────────
+personalization=# 10. PERSONALIZATION
+personalize=# 10. PERSONALIZATION
+secrets=## secrets.fish
+local-config=## local.fish
+
+# ── Section 11: Viewing This Manual ──────────────────────────
+viewing=# 11. VIEWING THIS MANUAL
+manual=# 11. VIEWING THIS MANUAL
 ov=## With ov (recommended)
 man-page=## As a man page (if compiled)
 manpage=## As a man page (if compiled)