Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@docs/DRIVERS.md`:
- Around line 27-35: The fenced code block containing the ASCII architecture
diagram that starts with "internal/cli   internal/tui     presentation (Cobra ·
Bubble Tea)" is missing a language tag and triggers markdownlint MD040; update
that triple-backtick fence to include a language identifier (e.g., change ``` to
```text) so the block becomes a text code block and the MD040 warning is
resolved.

In `@internal/cli/sync.go`:
- Around line 30-36: The CLI currently defaults --stream to true and
preflight-checks app.CapNativeStream (in the block referencing deps, fromName,
toName), which mismatches internal/app/sync.go where opt.Stream is ignored and
Sync always uses io.Pipe; to fix, change the CLI so it does not require
NativeStream by default: set the --stream flag default to false (or remove the
preflight check), and only call app.RequireCapability(deps, name,
app.CapNativeStream) when you actually intend to use native driver streaming
(i.e., when opt.Stream is true AND the code path will invoke the driver's native
stream API); reference opt.Stream, Sync in internal/app/sync.go, and
app.CapNativeStream/app.RequireCapability when making the conditional.

In `@internal/driver/_testing/suite.go`:
- Around line 81-104: The Cancel_PropagatesToSubprocess test
(Cancel_PropagatesToSubprocess) assumes conn.Backup spawns a long-running
pg_dump and cancels after 150ms, but a small dataset from
BackupRestore_Roundtrip can let pg_dump finish early; to fix, make the subtest
create a larger dump workload before starting conn.Backup (e.g., insert/seed
many more rows or otherwise inflate the DB in this subtest) so pg_dump is almost
certainly in-flight when cancel() is called, or alternatively relax the
assertion after the cancel to accept a nil error if the subprocess already
finished; update the Cancel_PropagatesToSubprocess test code around the
conn.Backup call to perform the seeding (or to change the post-cancel error
check) so it reliably exercises cancellation.