update CLAUDE.md, README.md and justfile

crates/lanspread-peer/ARCHITECTURE.md

@@ -5,6 +5,7 @@ the current idea: mDNS discovery, QUIC transport, on-demand metadata, and
 chunked file transfers.
 
 ## Goals (unchanged)
+
 - Local LAN discovery via mDNS.
 - QUIC + JSON messages for control, raw streams for file data.
 - UI drives operations through `PeerCommand`, peers remain headless.
@@ -13,6 +14,7 @@ chunked file transfers.
 ## Peer lifecycle and message flow
 
 ### 1) Startup and advertise
+
 - Start QUIC server.
 - Advertise via mDNS with TXT records:
   - `peer_id` (stable ID, not tied to IP)
@@ -21,7 +23,9 @@ chunked file transfers.
   - optional `hostname`
 
 ### 2) Discovery and handshake
+
 When a peer is discovered:
+
 1. Connect and send `Hello { peer_id, proto_ver, library_rev, library_digest, features }`.
 2. Receive `HelloAck { peer_id, proto_ver, library_rev, library_digest, features }`.
 3. If the remote `peer_id` is already known but the address changed, update it.
@@ -32,11 +36,13 @@ When a peer is discovered:
    - Otherwise request `LibrarySnapshot`.
 
 ### 3) Steady state
+
 - Any message updates `last_seen`.
 - Pings run only when idle (or on a longer interval), not every 5 seconds.
 - Library updates are pushed as deltas, debounced and coalesced.
 
 ### 4) Shutdown
+
 - Optional `Goodbye { peer_id }` lets others remove the peer quickly.
 - If a peer vanishes without goodbye, stale timeout + ping removal handle it.
 - Goodbye is a hint, never required for correctness.
@@ -44,20 +50,24 @@ When a peer is discovered:
 ## Library sync protocol
 
 ### Summary and snapshot
+
 - `LibrarySummary { library_rev, library_digest, game_count }`
 - `LibrarySnapshot { library_rev, games: Vec<GameSummary> }`
 
 ### Delta updates
+
 - `LibraryDelta { from_rev, to_rev, added, updated, removed }`
 - `removed` is a list of game IDs.
 - Deltas are idempotent; ignore if `to_rev` <= known rev.
 
 ### GameSummary (concept)
+
 - `id`, `name`, `eti_version`, `size`, `downloaded`, `installed`
 - `manifest_hash` (hash of file list + sizes)
 - `availability` (e.g., `ready`, `downloading`, `local_only`)
 
 ## When peers broadcast their game list
+
 - Only on changes, not on a timer.
 - Use a short debounce (1-2 seconds) to coalesce bursts of filesystem events.
 - Send `LibraryDelta` to known peers; send `LibrarySummary` on new connections.
@@ -65,6 +75,7 @@ When a peer is discovered:
 ## Local game scanning: fast and low cost
 
 ### Strategy
+
 1. Maintain a persistent on-disk index (per game):
    - `manifest_hash`, total size, file list (optional), and a fingerprint
      (version.ini mtime, .eti mtime/size, local install dir presence).
@@ -73,6 +84,7 @@ When a peer is discovered:
    missed events.
 
 ### Fast-path scanning
+
 - On startup, list only top-level game directories.
 - For each game, read a cheap fingerprint:
   - `.eti` size + mtime
@@ -82,20 +94,24 @@ When a peer is discovered:
 - Only run a recursive scan for new or changed games.
 
 ### Result
+
 Most scans become O(number of game dirs), with full recursion only when needed.
 
 ## File manifests and downloads
+
 - Keep `GetGame`/manifest requests, but keyed by `manifest_hash` so repeated
   calls can be skipped when unchanged.
 - Downloads remain chunked QUIC streams with the existing integrity checks.
 
 ## Fault tolerance rules
+
 - Every peer is keyed by `peer_id`, not by IP address.
 - `library_rev` is monotonic and guards against out-of-order updates.
 - Any mismatch or missing delta falls back to `LibrarySnapshot`.
 - Loss of goodbye is harmless; stale timeout is authoritative.
 
 ## Roadmap from current design to this one
+
 1. Protocol updates in `lanspread-proto`:
    - Define `Hello`, `HelloAck`, `LibrarySummary`, `LibrarySnapshot`,
      `LibraryDelta`, and optional `Goodbye` messages.