chore(release): prepare 0.8.0

[zikolach]

Summary

• Bump @zylab/pirelay to 0.8.0
• Add comprehensive changelog entries for 0.8.0 and backfill 0.7.1/0.7.2
• Archive update-live-progress-across-messengers and sync canonical OpenSpec specs

Validation

• npm run typecheck
• npm test
• openspec validate --specs --strict
• openspec validate --changes --strict

Publish note

• npm publish is blocked locally by npm ENEEDAUTH; publish after merge from an authenticated npm session with: npm publish --access public

[Copilot]

Pull request overview

Prepares the PiRelay npm package for release 0.8.0 by bumping package versions, backfilling and extending release notes, and updating/archiving OpenSpec specifications describing cross-messenger live progress update behavior (Slack/Discord edit-in-place support with safe fallbacks).

Changes:

• Bumped npm package version from 0.7.2 to 0.8.0 (package + lockfile).
• Added changelog entries for 0.8.0 and backfilled 0.7.1 / 0.7.2.
• Synced canonical OpenSpec specs and archived the completed “update live progress across messengers” change set (proposal/design/tasks + extracted “added requirements”).

Reviewed changes

Copilot reviewed 6 out of 15 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
package.json	Bumps package version to 0.8.0.
package-lock.json	Keeps lockfile package version in sync (0.8.0).
CHANGELOG.md	Adds release notes for 0.8.0 and backfills 0.7.1/0.7.2.
openspec/specs/slack-runtime-client/spec.md	Adds requirement coverage for Slack progress message update support.
openspec/specs/discord-runtime-client/spec.md	Adds requirement coverage for Discord progress message edit support.
openspec/specs/relay-channel-adapters/spec.md	Specifies optional adapter capability for live progress update-in-place + fallback invariants.
openspec/specs/messenger-relay-sessions/spec.md	Specifies session-level semantics for in-place progress updates where supported.
openspec/changes/archive/2026-06-14-update-live-progress-across-messengers/.openspec.yaml	Adds archive metadata for the completed OpenSpec change.
openspec/changes/archive/2026-06-14-update-live-progress-across-messengers/proposal.md	Archives the change proposal narrative for progress updates across messengers.
openspec/changes/archive/2026-06-14-update-live-progress-across-messengers/design.md	Archives the design decisions and fallback model for progress update behavior.
openspec/changes/archive/2026-06-14-update-live-progress-across-messengers/tasks.md	Archives the completed task checklist and validation steps.
openspec/changes/archive/2026-06-14-update-live-progress-across-messengers/specs/slack-runtime-client/spec.md	Captures “added requirements” excerpt for Slack spec changes.
openspec/changes/archive/2026-06-14-update-live-progress-across-messengers/specs/discord-runtime-client/spec.md	Captures “added requirements” excerpt for Discord spec changes.
openspec/changes/archive/2026-06-14-update-live-progress-across-messengers/specs/relay-channel-adapters/spec.md	Captures “added requirements” excerpt for adapter contract changes.
openspec/changes/archive/2026-06-14-update-live-progress-across-messengers/specs/messenger-relay-sessions/spec.md	Captures “added requirements” excerpt for session progress semantics.