chore(release): v0.21.0 — every created issue needs an owner

[muqsitnawaz]

Release cut for #44 (merged). Mechanical: moves the [Unreleased] CHANGELOG block to [0.21.0] and re-pins install.sh to the new tag + checksum. No behavior change beyond what #44 already landed.

VERSION	v0.20.0 → v0.21.0
EXPECTED_SHA256	d68fe508cb19460d0f2a517062a7a66646525539a11caedaa4a15ae5b3717cbe

The checksum is of linear at origin/main@11c1ef3, which this PR does not modify — so the pin stays valid at the tag:

$ shasum -a 256 linear
d68fe508cb19460d0f2a517062a7a66646525539a11caedaa4a15ae5b3717cbe  linear

v0.21.0 gets tagged on the merge commit, matching how v0.20.0 was cut (tag points at the install.sh pin commit, d7e909b).

What ships

• linear create refuses to make an unassigned issue and explains why. --force is the deliberate escape hatch. Three paths now fail closed: --assign none, an --assign value matching no human, and an unresolvable API key owner.
• --from-file bulk output no longer corrupts its tab-separated records — titles and echoed --assign values are escaped.

Full detail and the non-author review verdict: #44.

[prix-cloud]

VERDICT: APPROVE

Code Reviewer

Verdict: Ready to merge

Build: No build step — linear binary is pre-built, tests import the Python script directly.
Tests: 145/145 passed (0.024s)

Changes

File	Δ	What
CHANGELOG.md	+2/−0	Move [Unreleased] to [0.21.0] - 2026-09-05
install.sh	+2/−2	Bump VERSION to v0.21.0, update EXPECTED_SHA256

Verified

• Checksum match: shasum -a 256 linear = d68fe508cb19460d0f2a517062a7a66646525539a11caedaa4a15ae5b3717cbe ✅ — matches the PR's pin.
• Binary version: reports linear-cli 0.20.0 (pre-release; binary is not rebuilt in this PR, only the install pin is updated).
• Tests: all 145 pass.
• CHANGELOG format: consistent with Keep a Changelog convention and the repo's existing entries.
• No stale link references: the changelog doesn't use reference-style links for version headings, so no [unreleased]: or [0.21.0]: definition is needed.

Clean mechanical release cut. No issues.

---

Reviewed by Code Reviewer — actually ran the build and tests on this branch.

[prix-cloud]

VERDICT: APPROVE

Code Reviewer

Verdict: Ready to merge — mechanical release cut, no behavioral changes.

Build: Not applicable (Python script, no build step)
Tests: 145/145 passed locally (unittest); CI all green (unittest ×2, CodeQL, Analyze)

Changes verified

File	Change	Status
CHANGELOG.md	Moves [Unreleased] block → [0.21.0] - 2026-09-05	✅ Correct — follows the established pattern from v0.20.0
README.md	Pins from v0.18.0 → v0.21.0 (2 URLs)	✅ Correct
install.sh	VERSION: v0.20.0 → v0.21.0; EXPECTED_SHA256 updated	✅ Verified — checksum matches live binary: d68fe508cb…

What was confirmed

• Checksum verified: sha256sum linear produces the exact value in the new EXPECTED_SHA256 (d68fe508cb19460d0f2a517062a7a66646525539a11caedaa4a15ae5b3717cbe).
• Tests green: All 145 tests pass on this branch. No source changes — the test suite behavior is unchanged from the v0.20.0 cut.
• CI green: 5/5 checks pass on the PR.
• No source drift: The linear binary is identical to what's on origin/main@11c1ef3 (the PR only touches CHANGELOG.md, README.md, install.sh).
• No stubs, no env-var additions, no config drift: The changes are purely mechanical version/checksum bumps. No new symbols, no behavioral changes.

---

Reviewed by Code Reviewer — actually ran the tests and verified the checksum on this branch.

[muqsitnawaz]

Non-author review — verdict: READY TO MERGE

Reviewed by the code-reviewer subagent (non-author). The one catastrophic failure mode here is a wrong checksum — install.sh fails closed, so a bad pin bricks curl | sh for every new install. The reviewer computed it independently rather than trusting the PR body:

$ shasum -a 256 linear
d68fe508cb19460d0f2a517062a7a66646525539a11caedaa4a15ae5b3717cbe  linear

Exact match against install.sh:11.

Also verified:

• git diff origin/main...HEAD -- linear is empty — this PR doesn't touch the file it pins.
• No drift possible between now and tag time: linear's last-touching commit (11c1ef3) is the current tip of origin/main, so any merge strategy carries an identical blob to the tag.
• CHANGELOG is correct Keep-a-Changelog form — [Unreleased] preserved and empty, [0.21.0] - 2026-09-05 inserted, no content moved or dropped.
• Repo-wide grep for v0.20.0 / LINEAR_CLI_VERSION / LINEAR_CLI_SHA256 / the old 40e95dd4 hash found no other pin needing a bump.
• Semver: this project has never left 0.x across 27 tags, and prior behavior changes shipped as minor bumps. Under SemVer §4 a major bump isn't required for 0.x. Minor is consistent with precedent.

Review finding, fixed in this PR

README install snippets were stale at v0.18.0 (README.md:33,39) — bumped every release through v0.18.0, then missed for v0.19.0, v0.19.1, and v0.20.0. Anyone following the "Preferred" install path was getting a build three releases behind, and would have gotten one missing this release's owner guard. Both snippets now point at v0.21.0. The linear checksum is unchanged by that edit (re-verified above).

CI green on the head commit: Analyze (actions), Analyze (python), CodeQL, unittest ×2.

Tagging v0.21.0 on the merge commit, matching how v0.20.0 was cut.