chore(v2): lint pass — black + ruff auto-fix + mypy regressions (#29 v1.1)

Pre-merge lint hygiene on the PR #30 touched files:

- `black` reformatted 9 files (cassette_transport, crud, models, tasks,
  views_api, nip44, all 3 cassette test files, migrations). Cosmetic:
  line lengths, trailing commas, multi-line argument layout.
- `ruff check --fix` cleared 176 of 202 errors auto-fixed. Mostly
  `UP006` `typing.Optional` → `| None` modernization, `I001` import
  sort order, `UP035` typing-extensions cleanup.
- Two new mypy regressions introduced by the migration commit dcb7de0
  fixed:
  - `crud.py:apply_bootstrap_state` — annotated `existing_first: dict
    | None` on the dedup fetch.
  - `tasks.py:_cassette_consumer_tick` — `# type: ignore[arg-type]` on
    the `nostr_client.relay_manager.add_subscription` call; nostrclient's
    upstream typing declares `list[str]` for filters but the actual
    Nostr protocol takes `list[<filter-dict>]`. The runtime accepts it
    (live smoke at 13:43Z dispatched `nip44_decrypt` cleanly through
    this subscription); the typing mismatch is upstream's.

Remaining lint state, intentionally not addressed in this commit
(all pre-existing baseline, not regressions):
- 8 mypy errors in `calculations.py` + the unchanged-by-this-PR parts
  of `crud.py` — pre-existing on v2-bitspire.
- 26 ruff style warnings: 14 are N805 false-positives on Pydantic
  validators (`cls` first-arg is correct for `@validator`-decorated
  methods); 4 are N818 exception-name-suffix preferences on my new
  exception classes (renaming would touch many call sites; keep
  `OperatorIdentityMissing` / `SignerUnavailable` / `RelayUnavailable`
  / `_NostrclientUnavailable` as-is for clarity); 5 are E501 line-too-
  long on docstrings (the long lines are formatted for clarity);
  1 RUF002 unicode-minus in a docstring.

Tests: 155 passed, 1 pre-existing async-plugin failure unchanged.
Live smoke (both publish + consume directions through the bunker)
unaffected — this is purely a code-style pass.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

migrations.py

@@ -474,9 +474,7 @@ async def m006_rename_to_canonical_sat_vocabulary(db):
     ]
     for table, old_col, new_col in renames:
         try:
-            await db.fetchone(
-                f"SELECT {old_col} FROM satoshimachine.{table} LIMIT 1"
-            )
+            await db.fetchone(f"SELECT {old_col} FROM satoshimachine.{table} LIMIT 1")
         except Exception:
             # old column doesn't exist; either rename already landed or
             # m001 produced the canonical schema directly on fresh install.
@@ -496,15 +494,11 @@ async def m006_rename_to_canonical_sat_vocabulary(db):
     ]
     for table, col in drops:
         try:
-            await db.fetchone(
-                f"SELECT {col} FROM satoshimachine.{table} LIMIT 1"
-            )
+            await db.fetchone(f"SELECT {col} FROM satoshimachine.{table} LIMIT 1")
         except Exception:
             # column doesn't exist; either already dropped or never present.
             continue
-        await db.execute(
-            f"ALTER TABLE satoshimachine.{table} DROP COLUMN {col}"
-        )
+        await db.execute(f"ALTER TABLE satoshimachine.{table} DROP COLUMN {col}")
 
 
 async def m005_lock_deposit_currency_to_machine_fiat_code(db):
@@ -606,8 +600,7 @@ async def m008_flip_cassette_configs_pk_to_position(db):
         # Probe: does the old PK shape still exist? If state_denomination
         # column already exists, m008 already ran — no-op.
         await db.fetchone(
-            "SELECT state_denomination FROM satoshimachine.cassette_configs "
-            "LIMIT 1"
+            "SELECT state_denomination FROM satoshimachine.cassette_configs " "LIMIT 1"
         )
         return
     except Exception:
@@ -649,6 +642,5 @@ async def m008_flip_cassette_configs_pk_to_position(db):
 
     await db.execute("DROP TABLE satoshimachine.cassette_configs")
     await db.execute(
-        "ALTER TABLE satoshimachine.cassette_configs_new "
-        "RENAME TO cassette_configs"
+        "ALTER TABLE satoshimachine.cassette_configs_new " "RENAME TO cassette_configs"
     )