feat(memory): dual-pool memory namespace, FTS search, and prompt injection

Add a virtual memory namespace backed by SQLite, surfaced through the
fs-tools, with private (per-user) and shared (system) stores.

Storage
- `memory_docs` owner table + external-content FTS5 index with sync triggers.
- `db/memory_docs.rs` accessor: get / upsert / list / search (bm25+snippet) / delete.

Routing (tools/fs)
- `classify_memory` splits paths on the raw first component; `..` clamps inside
  the store, never escaping to disk.
- read/write/list/edit/insert/replace/search_file route `user-memory/` to the
  owner pool and `shared-memory/` to the system pool (a singleton captured in
  `register_all`); every other path stays on disk. Each tool extracts a pure
  transform shared between its disk and memory paths.
- New `memory_search` tool over the FTS index (scope private/shared/all),
  with a sanitised FTS5 query. grep_files stays disk-only.

Approval
- `user-memory/*` allow (read+write); `shared-memory/*` reads allow,
  writes require approval so the agent can't silently push one person's data
  into shared memory. `memory_search` allowed via a path-less rule.
- migrate away the old `memory/*` and blanket `shared-memory/*` rows.

Prompt injection
- `MessageBuilder::load_inject_memory` reads `user-memory/` (owner pool) and
  `shared-memory/` (system pool) inject entries from SQLite; disk paths
  unchanged. The system pool is threaded ChatSessionManager -> handler ->
  MessageBuilder.
- main and project-coordinator inject `user-memory/index.md` +
  `shared-memory/index.md`; common/memory.md rewritten for the two stores.

agents/main/AGENT.md

@@ -2,11 +2,9 @@
 
 You are an extremely powerful general-purpose personal assistant. You help the user with any task — research, writing, planning, analysis, coding, or anything else they bring to you.
 
-Your personality and tone are defined in `data/memory/SOUL.md`. If the file exists, it is automatically injected into your system context — look for it at the end of this prompt.
-
 Think outside the box: you can use tools, write and execute Python scripts on the fly, or even modify your own source code.
 
-The `data/` directory (inside your working directory) is your own space — write there freely; you have permission to create and modify anything under it. **Default to `data/` for everything you produce**: generated files, notes, one-shot scripts, downloads, and persistent memory (e.g. `data/memory/`, `data/notifications.md`). When a path is relative, prefix it with `data/` — a bare filename lands in the project root, which is not where your working files belong. Write **outside** `data/` (the project root, `src/`, `web/`, `agents/`, config, …) only when a specific, well-defined goal genuinely requires it and cannot be accomplished within `data/`.
+The `data/` directory (inside your working directory) is your own space — write there freely; you have permission to create and modify anything under it. **Default to `data/` for everything you produce**: generated files, notes, one-shot scripts, downloads. When a path is relative, prefix it with `data/` — a bare filename lands in the project root, which is not where your working files belong. (Persistent **memory** is separate: durable facts go to `user-memory/` or `shared-memory/`, not under `data/` — see the Memory section.) Write **outside** `data/` (the project root, `src/`, `web/`, `agents/`, config, …) only when a specific, well-defined goal genuinely requires it and cannot be accomplished within `data/`.
 
 You have access to tools, persistent memory system and sub agents. Use both proactively. Sub agents also help to keep your context windows small and concise.
 
@@ -113,7 +111,7 @@ Configuration tools are hidden by default to keep context small. Call `activate_
 
 ## Memory reminder
 
-Sessions are temporary — the user can close and start a new one at any moment. **Context alone is not enough.** If something is worth remembering, write it to a file in `data/memory/` immediately. If it stays only in context, it is gone forever when the session ends.
+Sessions are temporary — the user can close and start a new one at any moment. **Context alone is not enough.** If something is worth remembering, save it to `user-memory/` immediately (or `shared-memory/` if it's meant for the whole group). If it stays only in context, it is gone forever when the session ends.
 
 ---
 

agents/main/meta.json

@@ -1,9 +1,9 @@
 {
   "name": "Main Assistant",
-  "description": "General-purpose assistant: helps the user with any task using tools, and persists all relevant information in data/memory",
+  "description": "General-purpose assistant: helps the user with any task using tools, and persists all relevant information in memory",
   "friendly_description": "Your general-purpose assistant — helps with any task and remembers what matters in memory.",
   "type": "chat",
-  "inject_memory": ["data/memory/index.md", "data/memory/SOUL.md"],
+  "inject_memory": ["user-memory/index.md", "shared-memory/index.md"],
   "icon": "icon.png",
   "strength": "average"
 }