Contacts: postal-address support via vCard ADR, keep tool prompt minimal

Closes the gap that pushed the agent into manage_memory when the user
pasted an address and said 'save this for X'. manage_contact now
accepts an optional address arg end-to-end:

- routes/contacts_routes.py:
  - _normalize_contact carries an 'address' field
  - _build_vcard emits ADR:;;<address>;;;; (street component of the
    RFC-6350 7-part ADR), only when address is non-empty
  - _parse_vcards reads ADR, joins non-empty components with ', '
  - _create_contact and _update_contact thread address through;
    update preserves existing address when caller passes empty
- src/tool_implementations.py do_manage_contact:
  - add accepts address; require at least name+address or email
    (was: email required) so address-only contacts are addable
  - update accepts address; require name OR emails OR address
- src/tool_schemas.py: schema gets a single 'address' string field
- src/tool_index.py + src/agent_loop.py: descriptions get one
  'address' arg mention and a 'use this for save-X-for-person /
  address pastes / phone-with-name' steering line. Net: a few
  bytes added, not a paragraph.

Also: removed a stray name from the schema's manage_contact example
strings ('save Jonathan's email…') — no real names in the codebase.

src/tool_index.py

@@ -114,7 +114,7 @@ BUILTIN_TOOL_DESCRIPTIONS: Dict[str, str] = {
     "mark_email_read": "Mark an email as read or unread by toggling the \\Seen flag.",
     "bulk_email": "Perform one action on many emails at once. Use for delete all those, archive these, mark all read, move spam to junk. Takes explicit UIDs from list_emails or all_unread=true. Always pass account for Gmail/work/custom mailbox results.",
     "resolve_contact": "Look up a contact's email address by name. Searches CardDAV address book and sent email history. Use when the user says 'message [name]', 'email [name]', or 'send to [name]' without an email address.",
-    "manage_contact": "Save / update / delete / list address-book contacts (CardDAV). This is the right tool whenever the user is storing info about a specific OTHER person — their email, phone number, postal/mailing/street address, birthday, role at a company. Examples of phrasings that should land here: 'save this for <person>', 'save it for <person>', 'remember <person>'s address / phone / email', 'add <person> to contacts', 'update <person>'s email', 'delete <person> from contacts'. If the message contains a postal address, street, city, ZIP/postal code, or phone number alongside a person's name, use manage_contact — NOT manage_memory. Action=list returns the uid needed for update/delete. Do NOT use for facts about the USER themselves ('my name is X', 'I live at Y'); those are manage_memory.",
+    "manage_contact": "Save / update / delete / list address-book contacts (CardDAV). Use for info about ANOTHER person — name, email, phone, postal address. Args: action=list|add|update|delete, name, email, phones, address, uid (from list). For 'save this for <person>' / address pastes / phone numbers next to a name, this is the right tool — NOT manage_memory. Do NOT use for facts about the USER ('my name is X'); those are manage_memory.",
     "manage_notes": "Create and manage notes and checklists (Google Keep-style). ALWAYS use this for note/todo/checklist/reminder creation — NEVER hit /api/notes via app_api. Accepts natural-language `due_date` like 'tomorrow at 9am' or '11pm today' (parsed in the USER'S timezone). The due_date IS the reminder — it fires a notification at that time, so do NOT also create a calendar event for the same reminder. Set colors, labels, pin, archive. Do NOT use manage_memory for note content.",
     "manage_calendar": "Calendar event management: list, create, update, delete. Each event can carry a tag/category (event_type — work/personal/health/travel/meal/social/admin/other) and importance (low/normal/high/critical). Resolve today/tomorrow using the Current date and time context, then use ISO datetimes in the user's local wall time; supports all-day events. For event reminders/alarms, pass reminder_minutes; this creates the Notes reminder, so do not also call manage_notes for the same reminder.",
     "download_model": "Download a HuggingFace model to a local or remote server. Specify repo_id (e.g. 'Qwen/Qwen3-8B'), optional server host, and optional include filter for specific files.",