fix: stop hermes update from nagging about llm-wiki's wiki.path (#11222)

llm-wiki was the only shipped skill using metadata.hermes.config, which
caused 'hermes update' and 'hermes config migrate' to prompt for a wiki
directory on every run — even for users who have never touched the skill
— because 'enabled' is opt-out (all shipped skills count as enabled unless
explicitly disabled). Declining the prompt didn't persist anything, so
the nag fired again on every update.

Switch llm-wiki to the env var + runtime default pattern that obsidian and
google-workspace already use: WIKI_PATH env var, default $HOME/wiki. No
prompting infrastructure, no config.yaml touch, no nag loop.

Changes:
- skills/research/llm-wiki/SKILL.md: remove metadata.hermes.config,
  document WIKI_PATH env var in the Wiki Location section, update the
  orientation snippet and initialization guidance.
- Docs: replace llm-wiki's wiki.path examples with a generic 'myplugin.path'
  placeholder across configuration.md, features/skills.md, and
  creating-skills.md so users don't try to set skills.config.wiki.path
  expecting llm-wiki to use it.
- skills-catalog.md: mention WIKI_PATH instead of skills.config.wiki.path.

E2E verified: discover_all_skill_config_vars() and get_missing_skill_config_vars()
both return 0 entries after this change, so the prompt branch in migrate_config()
no longer fires.

The metadata.hermes.config feature stays in place for third-party skills
that genuinely need structured config, but built-ins now prefer env vars.

website/docs/developer-guide/creating-skills.md

@@ -186,18 +186,18 @@ Skills can declare non-secret settings that are stored in `config.yaml` under th
 metadata:
   hermes:
     config:
-      - key: wiki.path
-        description: Path to the LLM Wiki knowledge base directory
-        default: "~/wiki"
-        prompt: Wiki directory path
-      - key: wiki.domain
-        description: Domain the wiki covers
+      - key: myplugin.path
+        description: Path to the plugin data directory
+        default: "~/myplugin-data"
+        prompt: Plugin data directory path
+      - key: myplugin.domain
+        description: Domain the plugin operates on
         default: ""
-        prompt: Wiki domain (e.g., AI/ML research)
+        prompt: Plugin domain (e.g., AI/ML research)
 ```
 
 Each entry supports:
-- `key` (required) — dotpath for the setting (e.g., `wiki.path`)
+- `key` (required) — dotpath for the setting (e.g., `myplugin.path`)
 - `description` (required) — explains what the setting controls
 - `default` (optional) — default value if the user doesn't configure it
 - `prompt` (optional) — prompt text shown during `hermes config migrate`; falls back to `description`
@@ -208,8 +208,8 @@ Each entry supports:
    ```yaml
    skills:
      config:
-       wiki:
-         path: ~/my-research
+       myplugin:
+         path: ~/my-data
    ```
 
 2. **Discovery:** `hermes config migrate` scans all enabled skills, finds unconfigured settings, and prompts the user. Settings also appear in `hermes config show` under "Skill Settings."
@@ -217,14 +217,14 @@ Each entry supports:
 3. **Runtime injection:** When a skill loads, its config values are resolved and appended to the skill message:
    ```
    [Skill config (from ~/.hermes/config.yaml):
-     wiki.path = /home/user/my-research
+     myplugin.path = /home/user/my-data
    ]
    ```
    The agent sees the configured values without needing to read `config.yaml` itself.
 
 4. **Manual setup:** Users can also set values directly:
    ```bash
-   hermes config set skills.config.wiki.path ~/my-wiki
+   hermes config set skills.config.myplugin.path ~/my-data
    ```
 
 :::tip When to use which