docs: cross-link write-approval gate from skills, configuration, and slash-command docs (#43801)

The memory/skill write-approval gate (#38199, #43354, #43452) was only
documented inside features/memory.md. Surface it everywhere users will
actually look:

- features/skills.md: new 'Gating agent skill writes' section under
  skill_manage, with the staging semantics, review commands, and the
  distinction from skills.guard_agent_created
- configuration.md: memory.write_approval added to the Memory
  Configuration block; new 'Write approval for skill writes' subsection
  next to the guard_agent_created scanner
- reference/slash-commands.md: /memory and /skills review subcommands in
  both the CLI and messaging tables; Notes updated since /skills
  pending/approve/reject/diff/approval now works on the gateway
- features/memory.md: cross-link to the new skills section

website/docs/user-guide/features/memory.md

@@ -270,6 +270,7 @@ inline, but the full diff stays out-of-band:
 On a messaging platform, approve a skill from its gist + metadata, or open
 `/skills diff` on the CLI / dashboard / the staged file under
 `~/.hermes/pending/skills/<id>.json` when you want to read the whole change.
+Full details in [Gating agent skill writes](/user-guide/features/skills#gating-agent-skill-writes-skillswrite_approval).
 
 
 ## External Memory Providers

website/docs/user-guide/features/skills.md

@@ -401,6 +401,43 @@ The agent can create, update, and delete its own skills via the `skill_manage` t
 The `patch` action is preferred for updates — it's more token-efficient than `edit` because only the changed text appears in the tool call.
 :::
 
+### Gating agent skill writes (`skills.write_approval`)
+
+By default the agent writes skills freely — including from the [background
+self-improvement review](/user-guide/features/memory#controlling-memory-writes-write_approval)
+that runs after a turn. If you'd rather approve every skill write first
+(small models that misjudge what they learned, secure environments, or just
+wanting eyes on the self-improvement loop), turn on the write-approval gate:
+
+```yaml
+skills:
+  write_approval: false     # false = write freely (default) | true = require approval
+```
+
+When `write_approval: true`, every `skill_manage` write (create / edit /
+patch / delete / write_file / remove_file) is **staged** instead of committed —
+a SKILL.md is too large to review inline, so staging applies regardless of
+whether the write came from a foreground turn or the background review.
+Staged writes survive restarts under `~/.hermes/pending/skills/` and are
+reviewed with the same familiar approve/deny flow as dangerous commands:
+
+```
+/skills pending             # list staged skill writes + a one-line gist each
+/skills diff <id>           # full unified diff (best viewed in CLI or dashboard)
+/skills approve <id>        # apply it (or 'all')
+/skills reject <id>         # drop it (or 'all')
+/skills approval on         # turn the gate on (or 'off') and persist it
+```
+
+The review surface works in the interactive CLI and on messaging platforms
+(diff output is truncated for chat bubbles — read the full diff on the CLI or
+in the pending JSON file). Memory writes have the same gate under
+`memory.write_approval` — see [Controlling memory writes](/user-guide/features/memory#controlling-memory-writes-write_approval).
+
+> The separate `skills.guard_agent_created` setting is a content scanner
+> (dangerous-pattern heuristics), not an approval gate — the two are
+> independent. See [Guard on agent-created skill writes](/user-guide/configuration#guard-on-agent-created-skill-writes).
+
 ## Skills Hub
 
 Browse, search, install, and manage skills from online registries, `skills.sh`, direct well-known skill endpoints, and official optional skills.