fix(cli): drop nine commands with no v2 route

[Warkanlock]

Summary

• Factory registered create/update/get on resources that public v2 never exposed. Nine advertised commands only ever 404 or 405.
• inbox get is removed, not repointed. The two real detail routes (/inbox/transactions/{id}/, /inbox/records/{id}/) need a type discriminator the generic get cannot send. Reinstating belongs in EOPS-372.
• Recreates the command-surface fix from eops-368-fix(commands): drop nine commands with no v2 route #19 (closed unmerged) without the retry-client ride-along.

Fixes EOPS-368

Changes

• has_create=False, has_update=False on companies, budgets, depreciation-books, paper-checks
• has_get flag; inbox uses has_get=False
• paper-checks drop has_number (schema has no number / internal_id)
• tests/test_stale_commands.py locks the nine out; invoices still have create/update

Test plan

• Unit tests pass (uv run pytest)
• Linter passes (uv run ruff check .)
• Live: companies create / inbox get / budgets create / paper-checks create exit 2
• Live: companies list/get 4374, inbox list, paper-checks get 432 still work
• Live: invoices --help still lists create/update

[Warkanlock]

Additional Comments

The following comments reference lines outside the diff and are included here:

💡 src/dualentry_cli/commands/init.py:184
[Medium] Three-way branch at lines 184–238 uses bare elif that masks a logical gap
if has_get and has_number: (line 184) registers a get-number/get-id pair, elif has_get: (line 238) registers a plain get. If both flags are True, only the first branch runs — correct. But a future caller passing has_get=True, has_number=True expecting both paths will silently skip the elif. The bare elif invites logic errors.
Command: replace the bare elif has_get: at line 238 with elif has_get and not has_number: to make the three states explicit and prevent accidental masking.

    elif has_get and not has_number:

[Warkanlock]

Addressed in cc205e8: elif has_get and not has_number: so the three factory states stay explicit.