feat(plugin): define canonical codingbuddy:* namespace policy (#1287)

Add namespace-policy.md documenting that all future commands must use
the codingbuddy:* prefix. Add namespacePolicy metadata to plugin.json.

Author: JeremyDev87

packages/claude-code-plugin/.claude-plugin/plugin.json

@@ -5,5 +5,11 @@
   "author": {
     "name": "JeremyDev87",
     "email": "soundbrokaz@kakao.com"
+  },
+  "namespacePolicy": {
+    "prefix": "codingbuddy",
+    "bareCommandsDeprecated": true,
+    "policyDoc": "docs/namespace-policy.md",
+    "note": "All new commands MUST use the codingbuddy:* namespace. Existing bare commands are migration targets."
   }
 }

packages/claude-code-plugin/docs/namespace-policy.md

@@ -0,0 +1,42 @@
+# CodingBuddy Namespace Policy
+
+## Policy Statement
+
+CodingBuddy does **NOT** ship new bare top-level slash commands. All future commands use the `codingbuddy:*` namespace. Existing bare commands will be migrated to namespaced equivalents.
+
+This policy prevents collisions with Claude Code built-in commands and clearly identifies CodingBuddy-owned functionality.
+
+## Canonical Command Mapping
+
+| Legacy (bare) | Namespaced              | Status           |
+| ------------- | ----------------------- | ---------------- |
+| `/plan`       | `/codingbuddy:plan`     | migration target |
+| `/act`        | `/codingbuddy:act`      | migration target |
+| `/eval`       | `/codingbuddy:eval`     | migration target |
+| `/auto`       | `/codingbuddy:auto`     | migration target |
+| `/buddy`      | `/codingbuddy:buddy`    | migration target |
+| `/checklist`  | `/codingbuddy:checklist` | migration target |
+
+### Migration Notes
+
+- Legacy bare commands remain functional during the transition period.
+- Once Claude Code fully supports the `plugin:command` namespace resolution, bare aliases will be removed.
+- Both forms invoke the same underlying command file in `commands/`.
+
+## Keyword Workflow Retention
+
+The following keywords remain as primary workflow shortcuts:
+
+- **PLAN** — enter planning mode
+- **ACT** — enter implementation mode
+- **EVAL** — enter evaluation mode
+- **AUTO** — enter autonomous cycle mode
+
+Keywords are **NOT** slash commands. They are workflow triggers detected by hooks and `parse_mode`. Keywords do not collide with any Claude Code namespace and require no migration.
+
+## Policy for New Commands
+
+1. All new commands **MUST** use the `codingbuddy:` prefix.
+2. No exceptions for "convenient" short names.
+3. Command files are placed in `commands/` and automatically discovered by the plugin system.
+4. The namespaced form (`codingbuddy:<name>`) is the canonical invocation.