Reapply "feat: add support for LTM metadata (#1281)" (#1338)

[Hweinstock]

This reverts commit 2d8b9d7.

original PR was approved.

I've manually tested some basic flows with the assumption @nborges-aws has done deeper testing + planned bug bashing later.

[github-actions]

Package Tarball

aws-agentcore-0.14.2.tgz

How to install

gh release download pr-1346-tarball --repo aws/agentcore-cli --pattern "*.tgz" --dir /tmp/pr-tarball
npm install -g /tmp/pr-tarball/aws-agentcore-0.14.2.tgz

[agentcore-devx-automation]

Claude Security Review: no high-confidence findings. (run)

[agentcore-cli-automation]

This is a clean reapply of #1281 — I verified the per-file diffs of the 15 source/doc files in this PR are byte-identical (in their +/- lines) to commit 44b5c2c (the original feature commit), so all the fixes from the original PR review (useEffect-based rehydration of indexed-key state, shared validateIndexedKeyName/constants between schema and TUI, indexed_key_count / has_indexed_keys telemetry on both MemoryPrimitive and useCreateMemory, key-name persistence on Esc-back from the type substep) are preserved.

The schema also still slots in cleanly against the post-revert mainline — MemorySchema and the IndexedKey* constants/regex live in agentcore-project.ts, and the new primitives/memory.ts only owns MemoryStrategy*, so there's no overlap or drift with the namespace-templates refactor that landed while this was reverted.

One blocker I want to flag before merge:

validate-pr-title is failing. The current title Reapply "feat: add support for LTM metadata (#1281)" (#1338) doesn't start with a conventional-commit type, and the amannn/action-semantic-pull-request check rejects it (failing run). Options:

• Retitle to e.g. feat: re-add support for LTM metadata (reapply #1281) (or similar — feat/fix/chore/revert are all accepted).
• Or apply the bot label, which the workflow's ignoreLabels config skips.

Otherwise looks good to merge.