feat: add server.sh bash management script (macOS/Linux)

Equivalent to server.ps1 for bash environments:
- start / stop / restart / status / logs [N|-f]
- Detached background process via nohup
- PID file in logs/ with live-process verification
- Port-based fallback detection via lsof
- Memory reporting (Linux /proc + macOS ps)
- Colour output with ANSI codes
- stderr error highlighting in status view
- Follow mode (-f) for live log tailing

README.md

@@ -488,6 +488,7 @@ Server-Sent Events endpoint for live UI updates.
   - [x] Dark / light theme toggle defaulting to OS colour-scheme preference.
   - [x] `default_wait_seconds` changed to fully server-controlled (agents can no longer override wait time).
   - [x] Non-blocking `server.ps1` management script (start / stop / restart / status / logs).
+  - [x] Non-blocking `server.sh` bash management script — identical feature set for macOS / Linux.
   - [x] MCP stateless/stateful mode configurable via `MCP_STATELESS` env var (default `true`).
   - [x] Per-agent generation counter prevents abandoned (timed-out) coroutines from silently consuming instructions meant for newer calls.
   - [x] `tests/test_wakeup.py` covers both immediate-wakeup timing and concurrent-call generation safety.
@@ -518,8 +519,9 @@ pip install -r requirements.txt
 python main.py
 ```
 
-Or use the included management script (recommended — non-blocking):
+Or use the included management scripts (recommended — non-blocking):
 
+**PowerShell (Windows)**
 ```powershell
 .\server.ps1 start      # start in background, logs to logs/
 .\server.ps1 stop       # graceful stop
@@ -530,6 +532,18 @@ Or use the included management script (recommended — non-blocking):
 .\server.ps1 logs 100   # show last 100 lines
 ```
 
+**Bash (macOS / Linux)**
+```bash
+chmod +x server.sh      # make executable once
+./server.sh start       # start in background, logs to logs/
+./server.sh stop        # graceful stop
+./server.sh restart     # stop + start
+./server.sh status      # PID, memory, tail logs
+./server.sh logs        # show last 40 stdout lines
+./server.sh logs -f     # follow logs live
+./server.sh logs 100    # show last 100 lines
+```
+
 The server starts on `http://localhost:8000` by default.
 
 | URL | Description |