feat(maestro-tui): wire --config flag + document tui in INSTALL.md (NAP-283)

- `RunConfig` grows a `config_path: Option<PathBuf>` field, plumbed from the
  umbrella binary's global `--config` flag through to `MaestroConfigFile`
  loading. Explicit `--config <path>` wins over `$MAESTRO_CONFIG` over the
  platform default; a missing file still falls back to shipped defaults.
- `docs/INSTALL.md` gains a "terminal UI" section: that `maestro tui` ships
  in the default feature set, how to opt out (`--no-default-features
  --features cli,daemon`), the `MAESTRO_DAEMON_URL` override, and a worked
  example of `[tui]` / `[tui.keymap.normal]` config pointing at the
  full action vocabulary in the design spec.
- Adds a thin-build line for `--features cli` (CLI-only client) and lists
  `tui` in the default-feature set.
- CLAUDE.md repo-layout block lists the new `maestro-tui` crate.

Closes the NAP-275 v1 epic.

CLAUDE.md

@@ -28,6 +28,7 @@ crates/
 ├── maestro-daemon/      # `maestro daemon` — tmux wrapper + WS endpoints (NAP-212, NAP-214)
 ├── maestro-registry/    # `maestro registry` — phone book + HTTP API (NAP-213, NAP-215)
 ├── maestro-web/         # standalone `maestro-web` browser UI (NAP-241, NAP-249)
+├── maestro-tui/         # `maestro tui` — ratatui session manager (NAP-275 epic)
 ├── maestro-installer/   # `maestro-install` wizard: cargo install + systemd (NAP-225)
 └── maestro-e2e/         # cross-process integration tests (NAP-217)
 web/                     # browser SPA (NAP-218)

crates/maestro-tui/src/lib.rs

@@ -22,6 +22,7 @@ pub mod state;
 pub mod tabs;
 pub mod terminal;
 
+use std::path::PathBuf;
 use std::time::Duration;
 
 use ratatui::backend::CrosstermBackend;
@@ -38,6 +39,10 @@ pub struct RunConfig {
     /// HTTP base URL of the local daemon, e.g. `http://127.0.0.1:7070`.
     /// No trailing slash.
     pub daemon_url: String,
+    /// Explicit `--config <path>` override from the umbrella binary's global
+    /// flag. When `None`, [`maestro_config::resolve_config_path`] picks the
+    /// default (`$MAESTRO_CONFIG` or `~/.config/maestro/config.toml`).
+    pub config_path: Option<PathBuf>,
 }
 
 #[derive(Debug, thiserror::Error)]
@@ -62,8 +67,13 @@ pub async fn run(cfg: RunConfig) -> Result<(), TuiError> {
     // Health check — fail fast if no daemon is reachable.
     health_check(&base_url).await?;
 
-    // Load runtime config from disk if present; fall back to defaults.
-    let cfg_file = match maestro_config::resolve_config_path() {
+    // Load runtime config: explicit `--config <path>` wins, then
+    // `$MAESTRO_CONFIG`, then the platform default. Missing file is fine —
+    // we fall back to shipped defaults.
+    let cfg_path = cfg.config_path.clone().map(Ok).unwrap_or_else(|| {
+        maestro_config::resolve_config_path().map_err(|e| TuiError::Config(e.to_string()))
+    });
+    let cfg_file = match cfg_path {
         Ok(path) => maestro_config::MaestroConfigFile::load_or_default(&path)
             .map_err(|e| TuiError::Config(e.to_string()))?,
         Err(_) => maestro_config::MaestroConfigFile::default(),

crates/maestro/src/main.rs

@@ -167,7 +167,11 @@ async fn dispatch(cli: Cli) -> Result<(), Box<dyn std::error::Error>> {
             let daemon_url = args
                 .daemon_url
                 .unwrap_or_else(|| "http://127.0.0.1:7070".to_string());
-            maestro_tui::run(maestro_tui::RunConfig { daemon_url }).await?
+            maestro_tui::run(maestro_tui::RunConfig {
+                daemon_url,
+                config_path: cli.config,
+            })
+            .await?
         }
     }
     Ok(())

docs/INSTALL.md

@@ -52,8 +52,8 @@ The binary lands in `~/.cargo/bin/maestro` — make sure that's on your `$PATH`.
 
 ## Thin builds for single-role hosts
 
-The default install pulls in everything. Registry-only and daemon-only hosts
-can opt out of unused dependencies:
+The default install pulls in everything (`cli` + `daemon` + `registry` + `tui`).
+Single-role hosts can opt out of unused dependencies:
 
 ```sh
 # Registry server — no tmux/PTY/jwt-verifier code:
@@ -63,10 +63,52 @@ cargo install --git https://git.naps.pt/naps62/maestro \
 # Daemon-only host — no embedded web assets, no registry HTTP surface:
 cargo install --git https://git.naps.pt/naps62/maestro \
   --no-default-features --features daemon --locked maestro
+
+# CLI-only client (no local daemon, no TUI):
+cargo install --git https://git.naps.pt/naps62/maestro \
+  --no-default-features --features cli --locked maestro
 ```
 
 The wizard always installs the default-feature build.
 
+## The terminal UI: `maestro tui`
+
+`maestro tui` is the keyboard-and-mouse driven terminal UI client. It ships
+in the default feature set, so a vanilla `cargo install maestro` builds it.
+Drop the `tui` feature to skip it on hosts that don't need the UI surface
+(`--no-default-features --features cli,daemon`).
+
+It talks only to the **local** `maestro daemon` over `http://127.0.0.1:7070`
+by default; peer daemons reach you transparently via the catalog mirror.
+Override the daemon URL with `--daemon-url` or `$MAESTRO_DAEMON_URL`.
+
+The `[tui]` section in `~/.config/maestro/config.toml` (or whatever path you
+pass via the global `--config` flag) controls the keymap. Shipped defaults
+cover every v1 action — only override what you want to change:
+
+```toml
+[tui]
+leader = "ctrl-a"            # one byte that escapes Insert mode
+chord_timeout_ms = 1000      # how long to hold a partial chord like `g`
+
+[tui.keymap.normal]
+"i"            = "EnterInsert"
+"s"            = "OpenSpawnModal"
+"x"            = "KillHighlighted"
+"?"            = "ShowHelp"
+"ctrl-t"       = "NewTab"
+"g t"          = "NextTab"
+"ctrl-w h"     = "FocusSidebar"
+"enter"        = "AttachHighlighted"
+
+[tui.keymap.insert]
+# (leader is added automatically as LeaveInsert; only override here when you
+# want extra Insert-mode bindings)
+```
+
+The full action vocabulary lives in
+`docs/superpowers/specs/2026-05-28-maestro-tui-design.md` §3.8.
+
 ## Adding the browser UI (optional)
 
 `maestro-web` is a separate binary that serves the SPA bundle and reverse-