fix(cli): fail loud at the remaining CLI_SAFE_EXCEPTIONS sites; timing-free process tests

[marlon-costa-dc]

Follow-up to #202. It resolves two rule violations: the remaining catch-and-normalize sites (fail loud), and tests that measured host timing instead of behaviour.

1. Remaining CLI_SAFE_EXCEPTIONS catches

This is the same violation class #202 removed from prompts. CLI_SAFE_EXCEPTIONS has no consumers left, so it is deleted.

Site	Before	After
u.Cli.cmd_validate_settings (_utilities/cmd.py)	ValueError/TypeError/KeyError became r.fail("Settings validation failed: …")	No catch. Any exception escapes with its cause.
u.Cli.tables_resolve_config (_utilities/tables.py)	Every listed type became r.fail with message only	Only the model's ValidationError (the declared outcome) becomes r.fail(…, exception=exc). Everything else escapes.
u.Cli.tables_render (_utilities/tables.py)	Renderer errors became r.fail_op("Table formatting", …)	No catch. Renderer exceptions escape.
u.Cli.process_mapping (_utilities/validation.py)	skip mode swallowed exceptions into a debug log and collect aggregated them	Removed together with t.Cli.MappingProcessor. Nothing in the workspace calls it.
cli.apply_to_config (services/cli_params.py)	Every listed type became r.fail with message only	Only a CliParamsConfig ValidationError becomes r.fail(…, exception=exc). params_apply failures remain owner r.fails. Everything else escapes.

Constants removed because nothing uses them now: CLI_SAFE_EXCEPTIONS, ERR_SETTINGS_VALIDATION_FAILED, OUTPUT_TABLE_FORMATTING_OPERATION.

Consumers (grep of every member in the workspace)

• process_mapping, MappingProcessor and CLI_SAFE_EXCEPTIONS have no consumers outside flext-cli.
• cmd_validate_settings, tables_resolve_config, tables_render and apply_to_config are called only inside flext-cli (services/cmd.py, services/tables.py, _utilities/formatters.py, services/_cli_parts/flextclicli_part_02.py).
• Other repos match only unrelated homonyms (u.Web.validate_settings, flext-core _validate_settings) or generated architecture docs.

2. Timing-sensitive runtime-process tests

• test_completion_before_wake_clear_returns_promptly is now …_ends_monitoring.
  • The trace holds the monitor at wake.clear() until the waiter has set process_done and wake. It waits without a timeout; the old 2s cap is gone.
  • A monitor that lost that wake-up would sleep until its deadline and report timed_out. So not outcome.timed_out is the proof. The elapsed < 2 assertion is removed.
• test_normal_root_exit_leaves_no_descendant:
  • The descendant writes its pid and process group to a pipe, then blocks on an Event.
  • The root does a blocking readline, records it, and exits.
  • The proof is that the pid and process group no longer exist when run_to_file returns.
  • Removed: file polling, the heartbeat, sleep(0.15), and the < 5s assertion.
  • Interpreters start with -I -S.
• No timeout was raised.

Local gates (worktree fix/cli-fail-loud-remaining)

• make gen twice: exit 0 both times, and the diff hash is the same after each run (fixed point).
• make check: exit 0 (Total: 1 Success: 1).
• make test-full:
  • Run 1: exit 2, 1 failed, 1192 passed, at load average ~25. The failure was test_file_tools_yaml.py::test_single_source_returns_requested_model, blocked in os.fsync for 36s during atomic_write_text_file (host I/O stall). It is not a test changed here. Both rewritten tests passed in that run.
  • Runs 2 and 3: exit 0 each, 1193 passed, at load average ~20. Both rewritten tests passed.

🤖 Generated with Claude Code

---

Summary by cubic

Follow-up to #202: makes the remaining exception-handling sites fail loud and rewrites two runtime-process tests so they assert behavior, not the host clock. Exceptions these call paths used to normalize into generic failures now escape with their cause; only the Pydantic ValidationErrors the callers declare as outcomes are still reported as failures, and callers that relied on the old normalized messages now see the underlying exception.

Fail loud at remaining catch sites

• cmd_validate_settings and tables_render no longer catch anything; renderer errors now propagate instead of becoming r.fail messages.
• tables_resolve_config and apply_to_config only report the model's ValidationError as a failure and now attach it via exception=exc; params_apply failures remain the r.fail results their owners produce.
• Removes process_mapping and MappingProcessor; their skip mode swallowed exceptions into a debug log and collect mode aggregated them, and nothing in the workspace calls them.
• Deletes the now-unused CLI_SAFE_EXCEPTIONS, ERR_SETTINGS_VALIDATION_FAILED, and OUTPUT_TABLE_FORMATTING_OPERATION constants.

Timing-free runtime-process tests

• The completion test holds the monitor at its first wake.clear() until the root waiter has set process_done and wake, so a lost notification would surface as timed_out; the elapsed < 2 assertion, the child sleep, and the 2s wait caps are gone.
• The descendant test has the child announce its pid and process group over a pipe and then block forever; the root reads the line and exits, and the test asserts the pid and process group no longer exist when run_to_file returns. File polling, the heartbeat, sleep(0.15), and the < 5s assertion are removed.
• Both scenarios start interpreters with -I -S.

^{Written for commit 8280536. Summary will update on new commits.}

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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