feat(dna): Group DNA per-group coordination DHT with Sweettest suite

[Soushi888]

Intent

Implement the Group DNA as the per-group coordination layer of the Lobby → Group → NDO hierarchy. Each group gets its own DHT via a cloned cell from a Group DNA template. The GroupView and GroupSidebar UI components are currently full stubs — this DNA replaces those stubs with real data without changing any component interfaces.

Unblocked by PR #103 (Lobby DNA).

Changes

Integrity zome (zome_group_integrity)

• GroupProfile — group name, description, created_at, initiator
• GroupMembership — agent membership record (join date, role in group)
• WorkLog — contribution record within the group context
• SoftLink — planning-level link to a resource or NDO (dashed border in UI)

Coordinator zome (zome_group) — 16 externs

• create_group, get_group, get_my_group, update_group
• join_group, leave_group, get_group_members, is_member
• log_work, get_work_logs, get_my_work_logs, delete_work_log
• create_soft_link, get_soft_links, delete_soft_link
• init

Lobby DNA refactor — NdoAnnouncement replaced by GroupAnnouncement

• announce_group replaces announce_ndo
• get_my_group_announcements, get_group_announcement_by_dna_hash replace the NDO announcement functions
• get_my_groups now returns real group data instead of a stub solo workspace

Shared crate

• GroupError added to crates/shared/src/errors.rs

happ.yaml

• group role added with deferred: true and clone_limit: 64 — infrastructure for cloned cells (cell creation flow is deferred to a follow-up PR)

Service layer

• group.service.ts stub replaced with real callZome implementation — GroupServiceTag interface unchanged (ADR-GROUP-03)
• cell.manager.ts extended with getGroupCellHandle to resolve a DnaHash to a group CellId

Tests

• 13-test Sweettest suite in dnas/group/tests/: group creation, get_group (fetch by hash), get_my_group, membership (join/leave/is_member/duplicate-join guard), work logs (group + per-agent query + delete), soft links (create + get + delete), update_group, and validation rejection cases (empty name, zero hours)
• Lobby Sweettest updated for GroupAnnouncement API

Decisions

Option	Rejected because
New app install per group	Conductor proliferation — cloned cell is lighter and avoids admin overhead
Store SoftLinks as EconomicEvents	SoftLinks are planning-only (dashed border); generating PPRs would misrepresent intent
Keep GroupGovernanceRule entry type	No externs, no tests — premature DHT commitment; removed before merge

How to test

bun run build:happ
CARGO_TARGET_DIR=target/native-tests cargo test --package group_sweettest --test group -- --test-threads 6

All 13 Sweettest assertions pass. Thread limit required: 13 tests × 2 conductors = 26 conductors; without --test-threads 6 the suite hits port exhaustion.

Documentation

• documentation/zomes/group_zome.md (new file) — Group DNA API reference
• documentation/zomes/lobby_zome.md — updated for GroupAnnouncement API
• documentation/zomes/architecture_overview.md — updated for multi-DNA structure
• documentation/API_REFERENCE.md, IMPLEMENTATION_STATUS.md, TEST_COMMANDS.md updated

Related

Related issues:

• Closes feat(dna): Group DNA per-group coordination DHT with Sweettest suite #101

• Depends on: feat(dna): Lobby DNA multi-network federation entry point with Sweettest suite #100 (Lobby DNA — merged via PR feat(dna): Lobby DNA multi-network federation entry point with Sweettest suite #103 ✅)

• Follow-up: feat(ui): wire Lobby DNA into UI — profile bar, NdoBrowser states, DHT profile sync #106 (wire Lobby DNA into UI — Group DNA feeds GroupView data)

[Soushi888]

Review pass — issues found and fixed (commit 1892ce5)

All 13 Sweettest assertions now pass (-- --test-threads 6).

Issues resolved

1. No-op hash validation in integrity zome
validate_group_membership and validate_soft_link both checked get_raw_39().is_empty() on ActionHash fields. ActionHash is always exactly 39 bytes — this check is structurally impossible to fail. Removed both guards; replaced with comments explaining that existence validation is not possible from the integrity context.

2. AgentToWorkLogs link committed with no getter
log_work created AgentToWorkLogs links on every write, but there was no get_my_work_logs extern to query them. Every write was a DHT commitment with no corresponding read path. Added get_my_work_logs(_: ()) -> Vec<WorkLog>.

3. GroupUpdates link type without update_group function
GroupUpdates was defined in LinkTypes and documented in the link types table, but no coordinator function used it. Following the same rationale that removed GroupGovernanceRule (no externs, no tests, premature DHT commitment), the correct fix here is the opposite: add update_group rather than remove the link, since profile updates are a natural use case. Added update_group with NotAuthor guard, mirroring the update_person pattern.

4. Stale TypeScript types
GroupGovernanceRule and GroupGovernanceRuleInput remained in packages/shared-types/src/group.types.ts after the Rust entry type was removed. Removed both; added UpdateGroupInput to match the new update_group extern.

5. Missing test coverage
Added 5 new Sweettest cases:

• duplicate_join_returns_already_member_error — the AlreadyMember guard existed but was untested
• empty_group_name_rejected — name validation path
• work_log_zero_hours_rejected — hours validation path
• get_my_work_logs_returns_own_logs — new get_my_work_logs extern
• update_group_changes_name — new update_group extern

6. Thread limit for all-tests run
13 tests × 2 conductors each = 26 concurrent Holochain conductors fails due to port exhaustion when run without a thread cap. Documented -- --test-threads 6 in TEST_COMMANDS.md and group_zome.md.

No regressions

All original 8 tests continue to pass. Build CI remains green.