chore: prepare release v1.8.0

[PiTrem]

Prepares the v1.8.0 release (current master is 1.7.2).

Changes

1. Version bump package.json 1.7.2 → 1.8.0 (matches the chore: Bump version … convention).
2. Clean dist/ rebuild — yarn compile in the CI Node image (node:22.23.1, matching publish_package.yml). Only 7 files changed: exactly the source files fix(lcms): resolve review regressions B1, B4–B7 on master #316 fixed, which merged to master without a dist rebuild — so the committed dist was stale by precisely that. The v1.8.0 tag now carries a single src-matching build. dist/__tests__ stays gitignored; no file additions/deletions.
3. CHANGELOG.md (new) — starts the convention; entries derived from git log v1.7.2..master.

Why keep dist/

dist/ is committed intentionally: main/module → dist/app.js, files: ["dist"], and chemotion_ELN consumes this repo as a GitHub-source dependency (no postinstall build). Removing it would break git-ref consumers, so this PR rebuilds rather than removes it.

Verification

• yarn compile clean (234 files); dist/*.js syntax-check OK.
• Full suite green in node:22.23.1: 76 suites / 621 tests.
• package.json version = 1.8.0.

After merge (release execution — not in this PR)

1. Tag the merge commit v1.8.0 and push.
2. Create the GitHub Release for v1.8.0 → publish_package.yml builds dist + publishes @complat/react-spectra-editor@1.8.0 to npm.