v0.9.0

✨ Added

• Errors are now easier to act on: human output prints the next-step hint (and a did-you-mean suggestion for unknown flags or commands), the JSON envelope carries those in a new suggestions field, and hints across the CLI were rewritten in plain language.

🪲 Fixed

• error envelopes now carry a complete, guarded taxonomy: read-only refusals emit code read_only, dry-run transport guards dry_run_blocked, wrong-shape ADF payloads adf_invalid (the raw json unmarshal text no longer leaks), issue-key expansion limits, ambiguous users and ambiguous boards their own codes, invalid --output values route through flag_value_invalid, every code ships a non-empty hint, a permanently deleted resource (HTTP 410) now exits 2 (not found) instead of 3, and exits 6 (canceled) / 7 (timeout) plus all emitted error fields are documented in the agent contract
• Several credential and 1Password error hints now point at the correct fix — including a 1Password failure on a build without 1Password support, and a login that can't reach Jira to verify, which previously suggested remediation that did not apply.

📜 Commits

• d34449b fix(cli): give every error a stable code and a non-empty hint
• eeb96bf test(cli): guard the error taxonomy contract
• 8294c60 refactor(errtax): add shared error-taxonomy package and registry
• b6a9263 refactor(cli): collapse MapError onto the registry-driven assembler
• b357208 test(cli): drive the taxonomy guard from the production registry
• a8424a9 feat(cli): surface error hints and suggestions in human output

Full Changelog: v0.8.4...v0.9.0