feat(console): list/regex read_until, serial error clarity; v0.3

read_until:
- 'expected' now accepts a list of values (succeeds on any match).
- new 'regex: true' flag: each pattern is a Python regex (re.search over a
  bounded tail, Console.REGEX_WINDOW). Reports which pattern matched.

Serial console robustness & clarity:
- failed open() raises a clear ETUMRuntimeError ("Serial device '…' does not
  exist." / permission hint) instead of a raw pyserial traceback.
- a console whose open failed is safely "not open" (init _thd=None +
  isOpened guards in readchar/read_nowait/close) — no more cascading
  AttributeError: '_thd' on subsequent read steps.
- action handlers: one-liner for expected (ETUMRuntimeError) errors, full
  traceback kept for unexpected ones. All console errors use testium
  exceptions (ETUMRuntimeError).

Flatpak: grant --device=all so serial adapters (/dev/ttyUSB*, /dev/ttyACM*)
are visible in the sandbox.

Validation: new read_until list/regex (match + no-match) cases in
items/console/test.tum.

Version: 0.3.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

DESIGN.md

@@ -302,6 +302,7 @@ The `testium_assist` editor extension is a thin LSP client that spawns `testium
 Both Flatpak and AppImage export `TESTIUM_VERSION` from a launcher (Flatpak: launcher script in `org.testium.Testium.yaml`; AppImage: `runtime.env` in `AppImageBuilder.yml`). `get_testium_version()` checks `/.flatpak-info` / `APPIMAGE` and reads `TESTIUM_VERSION` rather than relying on package metadata or repo introspection.
 
 ## Recent fixes / notable changes
+- `console` item — serial robustness + richer `read_until`: (1) a failed serial `open()` now raises a clear `ETUMRuntimeError` ("Serial device '…' does not exist." / permission hint) instead of dumping a pyserial traceback, and a console whose open failed is safely "not open" (init `_thd=None` + `isOpened` guards in `readchar`/`read_nowait`/`close`) so later reads no longer crash with `AttributeError: '_thd'`; the action handlers show a one-liner for expected (`ETUMRuntimeError`) errors and keep the full traceback for unexpected ones. (2) `read_until`'s `expected` now accepts a **list of values** (match any) and a new `regex: true` flag treats each pattern as a Python regex (`re.search` over a bounded tail — `Console.REGEX_WINDOW`; limitation: cost/memory bounded, so a match only after a very long stream or beyond the window won't fire). Flatpak manifest now grants `--device=all` so serial adapters (`/dev/ttyUSB*`, `/dev/ttyACM*`) are visible in the sandbox. Validation: new `read_until` list/regex cases in `test/validation/items/console/test.tum`.
 - Subprocess RPC startup handshake: the `py_func`/`lua_func`/`eval_proc` worker now picks its own port (`bind 0`), announces it on stdout (`__TESTIUM_RPC_PORT__=`), and the parent connects only after reading it. Fixes intermittent Windows `failed to connect : timeout` and the matching `wait_ready()` hang; removes the reserve/close/rebind race and `SO_REUSEADDR`. See "Subprocess RPC startup handshake".
 - `build_all.sh`: builds the four heavy channels in parallel (serial prep for the shared venv + wheel), results in completion order, Ctrl+C kills the whole job tree; `--ram` puts the build scratch on tmpfs (`/dev/shm`) + skips UPX for fast builds on USB/SD storage (Flatpak excluded — rofiles-fuse can't mount tmpfs). See the "Building all channels" section.
 - LSP across packaging channels: `testium lsp` (and the `testium_assist` editor extension that spawns it) now works from source, wheel, PyInstaller, Flatpak and AppImage. Two enablers — (1) action items declare a class-level `ACTIONS = {key: class}` registry (like `PARAMS`), so `lsp/schema.py` builds the full schema from class attributes with no `inspect.getsource`/AST (which broke under frozen PyInstaller); (2) the `[lsp]` extra (pygls) is wired into every full-app channel. `test/validation/lsp_check.py`, run by `run.sh` before the suite, asserts per-channel that `schema` keeps its actions and `lsp` answers `initialize`. See the matching architecture sections.