After devcontainer restart (cold-start), `bd --no-daemon show` failed to
find beads because:
1. Read-only commands skipped auto-import
2. Newly created DB had no issue_prefix set, causing import to fail
This fix enables seamless cold-start recovery by:
- Allowing read-only commands (show, list, etc.) to auto-bootstrap when
JSONL exists but DB doesn't
- Setting needsBootstrap flag when falling back from read-only to
read-write mode for missing DB
- Auto-detecting and setting issue_prefix from JSONL during auto-import
when DB is uninitialized
Fixes: gt-b09
Co-authored-by: Claude <noreply@anthropic.com>
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