feat: add claude wrapper that auto-links AGENTS.md as CLAUDE.md

New functions/claude.fish wraps the claude CLI. Before launch it checks the
current directory and the git project root; when CLAUDE.md is absent but
AGENTS.md is present, it creates a relative symlink CLAUDE.md -> AGENTS.md so
Claude Code picks up shared agent instructions without duplicating the file.
Arguments are forwarded verbatim.

Implemented as a C1 command shadow: when __fish_config_op_aliases (or the
master __fish_config_opinionated) is disabled, the call passes through to the
bare claude binary unchanged. Link-creation notices print to stderr in green.

Documents the new shadow in docs/fish-config.md (section 5.12 AI tools, C1
component reference table, and C1 summary list) and adds a claude-cli anchor
to docs/fish-config.index.

docs/fish-config.index

@@ -130,6 +130,7 @@ logs=### logs
 smart-exit=### smart_exit
 ai=## 5.12 AI and Developer Tools
 antigravity=### antigravity
+claude-cli=### claude
 claude=### claude-resume
 claude-docs=### claude-docs
 claude-pr=### claude-pr

docs/fish-config.md

@@ -1106,6 +1106,20 @@ Add -i (interactive confirmation) to destructive commands:
     file in the current directory, or opens an interactive fzf picker if no
     session file is found.
 
+### claude
+
+    Synopsis:  claude [args...]
+    Wrapper for the claude CLI. Before launching, checks the current
+    directory and the git project root for CLAUDE.md; when it is absent but
+    AGENTS.md is present, creates a relative symlink CLAUDE.md -> AGENTS.md
+    so Claude Code picks up shared agent instructions without duplicating
+    the file. All arguments are forwarded verbatim. Command shadow (C1):
+    when __fish_config_op_aliases (or the master) is disabled, the call is
+    passed through to the real claude binary unchanged.
+
+    claude
+    claude --resume
+
 ### claude-resume
 
     Synopsis:  claude-resume
@@ -1459,7 +1473,8 @@ but a category with an explicit truthy value remains enabled regardless.
                                     ping->prettyping, ssh->kitten,
                                     du->duf/dust, mkdir/bash wrappers,
                                     history timestamps, grep/cp/mv/wget
-                                    flag injection, help intercept
+                                    flag injection, help intercept, claude
+                                    AGENTS.md auto-link
     __fish_config_op_autoexec       Startup side-effects: Fisher
                                     bootstrap, theme apply, paru/yay
                                     wrapper generation, auto venv
@@ -1545,6 +1560,7 @@ all of these commands.
     grep/fgrep/egrep   forced --color=auto                    system grep variants
     dir / vdir         forced --color=auto                    system dir / vdir
     help config        intercepts "help config" → config-help fish builtin help
+    claude             auto-links AGENTS.md as CLAUDE.md before launch command claude
 
 When C1 is disabled, `rm` uses bare `command rm` with no wrapper — files
 are permanently deleted, not trashed. There is no intermediate safety net.