docs(website): dedicated page per bundled + optional skill (#14929)

Generates a full dedicated Docusaurus page for every one of the 132 skills
(73 bundled + 59 optional) under website/docs/user-guide/skills/{bundled,optional}/<category>/.
Each page carries the skill's description, metadata (version, author, license,
dependencies, platform gating, tags, related skills cross-linked to their own
pages), and the complete SKILL.md body that Hermes loads at runtime.

Previously the two catalog pages just listed skills with a one-line blurb and
no way to see what the skill actually did — users had to go read the source
repo. Now every skill has a browsable, searchable, cross-linked reference in
the docs.

- website/scripts/generate-skill-docs.py — generator that reads skills/ and
  optional-skills/, writes per-skill pages, regenerates both catalog indexes,
  and rewrites the Skills section of sidebars.ts. Handles MDX escaping
  (outside fenced code blocks: curly braces, unsafe HTML-ish tags) and
  rewrites relative references/*.md links to point at the GitHub source.
- website/docs/reference/skills-catalog.md — regenerated; each row links to
  the new dedicated page.
- website/docs/reference/optional-skills-catalog.md — same.
- website/sidebars.ts — Skills section now has Bundled / Optional subtrees
  with one nested category per skill folder.
- .github/workflows/{docs-site-checks,deploy-site}.yml — run the generator
  before docusaurus build so CI stays in sync with the source SKILL.md files.

Build verified locally with `npx docusaurus build`. Only remaining warnings
are pre-existing broken link/anchor issues in unrelated pages.

website/docs/user-guide/skills/bundled/note-taking/note-taking-obsidian.md

@@ -0,0 +1,86 @@
+---
+title: "Obsidian — Read, search, and create notes in the Obsidian vault"
+sidebar_label: "Obsidian"
+description: "Read, search, and create notes in the Obsidian vault"
+---
+
+{/* This page is auto-generated from the skill's SKILL.md by website/scripts/generate-skill-docs.py. Edit the source SKILL.md, not this page. */}
+
+# Obsidian
+
+Read, search, and create notes in the Obsidian vault.
+
+## Skill metadata
+
+| | |
+|---|---|
+| Source | Bundled (installed by default) |
+| Path | `skills/note-taking/obsidian` |
+
+## Reference: full SKILL.md
+
+:::info
+The following is the complete skill definition that Hermes loads when this skill is triggered. This is what the agent sees as instructions when the skill is active.
+:::
+
+# Obsidian Vault
+
+**Location:** Set via `OBSIDIAN_VAULT_PATH` environment variable (e.g. in `~/.hermes/.env`).
+
+If unset, defaults to `~/Documents/Obsidian Vault`.
+
+Note: Vault paths may contain spaces - always quote them.
+
+## Read a note
+
+```bash
+VAULT="${OBSIDIAN_VAULT_PATH:-$HOME/Documents/Obsidian Vault}"
+cat "$VAULT/Note Name.md"
+```
+
+## List notes
+
+```bash
+VAULT="${OBSIDIAN_VAULT_PATH:-$HOME/Documents/Obsidian Vault}"
+
+# All notes
+find "$VAULT" -name "*.md" -type f
+
+# In a specific folder
+ls "$VAULT/Subfolder/"
+```
+
+## Search
+
+```bash
+VAULT="${OBSIDIAN_VAULT_PATH:-$HOME/Documents/Obsidian Vault}"
+
+# By filename
+find "$VAULT" -name "*.md" -iname "*keyword*"
+
+# By content
+grep -rli "keyword" "$VAULT" --include="*.md"
+```
+
+## Create a note
+
+```bash
+VAULT="${OBSIDIAN_VAULT_PATH:-$HOME/Documents/Obsidian Vault}"
+cat > "$VAULT/New Note.md" << 'ENDNOTE'
+# Title
+
+Content here.
+ENDNOTE
+```
+
+## Append to a note
+
+```bash
+VAULT="${OBSIDIAN_VAULT_PATH:-$HOME/Documents/Obsidian Vault}"
+echo "
+New content here." >> "$VAULT/Existing Note.md"
+```
+
+## Wikilinks
+
+Obsidian links notes with `[[Note Name]]` syntax. When creating notes, use these to link related content.