[ngeorger]

Summary

Adds entire-agent-dsh, an external agent integration for DeepSeek Harness (DSH).

DSH has no repository-local hook command. The integration pairs with the
@sredevopsorg/dsh-entire
Host plugin: the plugin reads .entire/dsh-hooks.json and forwards lifecycle
events to entire hooks dsh <hook>. entire-agent-dsh resolves the native DSH
session log ($DSH_HOME/sessions/<project>/<session>/session.vN.jsonl.zstd),
decodes its concatenated Zstandard frames, and materializes a normalized JSONL
cache for Entire.

What it implements

• Hooks: session-start, turn-start, turn-end, compaction, session-end,
  subagent-start, subagent-end (the last two declared for forward
  compatibility; the host bridge does not emit them yet). Marker installation is
  idempotent and rewrites stale hook sets.
• Transcript analysis: line-position tracking, prompts (context-form
  injections excluded), modified files (write, edit, str_replace_editor,
  apply_patch), summaries, and per-call token usage.
• Compact transcripts: emits Entire Transcript Format v1 with inlined tool
  results and per-call usage/model.
• Session storage: normalized cache under $DSH_HOME/entire/sessions/, with
  tolerant zstd decoding, symlink-resolved lookup/containment, and safe filenames
  for unsafe/Windows-device session IDs.
• Resume: entire session resume re-frames a restored transcript into DSH's
  native store (rewriting header id/cwd to the current physical checkout)
  when no native generation exists. Existing live generations are never
  overwritten.

Verification

• gofmt, go vet, golangci-lint — clean.
• go test ./... — pass (unit tests cover paths, zstd/torn tails, hooks,
  analyzers, compact format, symlinked checkouts, native restore).
• external-agents-tests verify — all suites pass: hooks, mandatory, optional,
  subagent, transcript.
• scripts/verify-dsh.sh against Entire CLI 0.12.2 — creates a session,
  checkpoint, compact transcript, token usage, and Entire-Checkpoint trailer.
• Verified against a live DSH 0.2.2-rc.1 session on disk.

Dependency

github.com/klauspost/compress (BSD-3-Clause) for Zstandard decoding; a
doc/dependency_decisions.yml entry is included. The Entire CLI already uses the
same package.

Known limitations / follow-ups

• The DSH Host plugin is required for capture and checks the marker relative to
  the session workspace; start DSH at the repository root. The plugin also
  resolves entire/entire-agent-dsh from the Host PATH.
• The current bridge emits turn-start only for human/user/prompt sources.
  Scheduled/webhook/team turns need a companion change in dsh-plugins to widen
  the source-kind set.
• session-end depends on session/disposed, which long-lived Web Hosts may not
  emit.
• DSH has no interactive --resume; interactive resume remains opening the
  session in dsh web.
• Sessions above Entire's 10 MB subcommand stdout cap cannot be returned in one
  read-transcript call.

This is a new-agent integration; happy to adjust naming, capability choices, or
test wiring to match maintainer preferences.