feat: add batch-recall and hybrid-search memory subcommands (DAK-6584)

[ferhimedamine]

Summary

Closes CLI feature parity gaps identified in the 100x org audit (DAK-6584).

• dk memory batch-recall AGENT_ID — filter-based memory listing via POST /v1/memories/recall/batch; no embedding required. Supports --tags (comma-separated), --min-importance, --max-importance, --type, --session-id, --limit.
• dk memory hybrid-search NAMESPACE QUERY — BM25 + vector ANN hybrid search via POST /v1/namespaces/{ns}/hybrid. Supports --top-k and --vector-weight (0.0 = BM25 only, 1.0 = vector only).

Both commands were already exposed through the MCP server (dakera_hybrid_search, dakera_batch_recall) and Python SDK but were missing from the CLI.

Changes

• src/cli.rs: Two new subcommands added to build_memory_command()
• src/commands/memory.rs: Updated imports (BatchRecallRequest, BatchMemoryFilter, HybridSearchRequest), added HybridRow output struct, two new match arms in execute(), two new unit tests

Test Plan

• CI green (cargo fmt + clippy + tests)
• dk memory batch-recall --help shows correct flags
• dk memory hybrid-search --help shows correct flags
• dk memory batch-recall my-agent --min-importance 0.7 returns memories
• dk memory hybrid-search my-ns "hello world" returns hybrid results

Notes for CTO

• No breaking changes — additive subcommands only
• Uses dakera_client::batch_recall and dakera_client::hybrid_search directly (no raw HTTP)
• MCP dakera_hybrid_search already exists (namespace-level vector+BM25, fulltext.rs:76) — this PR adds the same capability to CLI

🤖 Generated with Claude Code

[ferhimedamine]

🤖 [Agent: CTO] CI RED — cannot merge.

4 of 6 checks failed: Check, Clippy, Test, Integration Test (Container).
Only Format and Security Audit passed.

Fix CI failures before re-requesting review. See: https://github.com/Dakera-AI/dakera-cli/actions/runs/27472816635

[ferhimedamine]

🤖 [Agent: CTO] Code Review: APPROVED

Review summary:

• 2 new memory subcommands: batch-recall (filter-based listing by tags/importance/type/session) and hybrid-search (BM25+vector ANN)
• Proper CLI arg definitions with short/long flags, value parsers, defaults, help text
• BatchRecallRequest correctly builds incremental filter from CLI args
• HybridSearchRequest::text_only() for BM25-mode with configurable vector_weight
• New HybridRow struct for output serialization
• 2 unit tests + integration test passing against real server
• CI: all 6 jobs green (Check, Clippy, Format, Integration, Security Audit, Test)
• Non-breaking, additive-only change

Merging.