docs: align command docs with shipped behavior (#2169)

- multi-{plan,execute,backend,frontend,workflow}.md: add an in-file
  prerequisite note for the external ccg-workflow runtime. README.md already
  warns these commands need codeagent-wrapper and the .ccg prompt tree, but
  users meeting them via the installed slash commands never see the README;
  the commands-core module still installs all five by default
- quality-gate.md: describe what scripts/hooks/quality-gate.js actually does.
  The doc advertised '/quality-gate [path] [--fix] [--strict]' with lint/type
  checks, but the script reads the file path from hook stdin JSON, toggles
  behavior via ECC_QUALITY_GATE_FIX / ECC_QUALITY_GATE_STRICT env vars, and
  runs formatters only (Biome/Prettier, gofmt, ruff format)
- claude-devfleet SKILL.md: add a Setup section pointing at the DevFleet
  server repository (github.com/LEC-AI/claude-devfleet, already disclosed in
  mcp-configs/mcp-servers.json) plus the SECURITY.md port-verification note;
  the skill previously assumed a running instance with no way to obtain one
- regenerate docs/COMMAND-REGISTRY.json for the quality-gate description

commands/quality-gate.md

@@ -1,33 +1,51 @@
 ---
-description: Run the ECC quality pipeline for a file or project scope and report remediation steps.
+description: Run the ECC formatter quality gate for a single file and report remediation steps.
 ---
 
 # Quality Gate Command
 
-Run the ECC quality pipeline on demand for a file or project scope.
+Operator entry point for the formatter quality gate that normally runs as the
+`post:quality-gate` PostToolUse hook (`scripts/hooks/quality-gate.js`).
+
+## How it actually works
+
+The gate is a single-file formatter check driven by hook input, not CLI flags:
+
+- The script reads the target from the hook's stdin JSON
+  (`tool_input.file_path`); it does not take a path argument.
+- Behavior toggles are environment variables:
+  - `ECC_QUALITY_GATE_FIX=true` - apply formatting fixes instead of check-only
+  - `ECC_QUALITY_GATE_STRICT=true` - log formatter failures as gate failures
+- Coverage by file type:
+  - `.ts/.tsx/.js/.jsx/.json/.md` - Biome `check` or Prettier `--check`,
+    whichever the project ships (JS/TS under Biome is skipped here because
+    `post-edit-format` already runs `biome check --write`)
+  - `.go` - `gofmt`
+  - `.py` - `ruff format`
+- Lint and type checks are not part of this gate. Use the `verification-loop`
+  skill or the language verification skills for lint/type/test pipelines.
 
 ## Usage
 
-`/quality-gate [path|.] [--fix] [--strict]`
+To run the gate manually against one file, pipe hook-style JSON into the
+script (set the env toggles first if you want fix or strict behavior):
 
-- default target: current directory (`.`)
-- `--fix`: allow auto-format/fix where configured
-- `--strict`: fail on warnings where supported
+```bash
+echo '{"tool_input":{"file_path":"src/example.ts"}}' \
+  | ECC_QUALITY_GATE_FIX=true node scripts/hooks/quality-gate.js
+```
 
-## Pipeline
-
-1. Detect language/tooling for target.
-2. Run formatter checks.
-3. Run lint/type checks when available.
-4. Produce a concise remediation list.
+Then report formatter findings and concrete remediation steps.
 
 ## Notes
 
-This command mirrors hook behavior but is operator-invoked.
+Hook wiring lives in `hooks/hooks.json` (`post:quality-gate`, profiles
+`standard`/`strict` via `run-with-flags.js`).
 
 ## Arguments
 
 $ARGUMENTS:
-- `[path|.]` optional target path
-- `--fix` optional
-- `--strict` optional
+
+- `[path]` optional file to check. The script itself takes no CLI
+  arguments - when a path is given, substitute it as `tool_input.file_path`
+  in the stdin JSON shown above before running the command