The authored component tree moves out of the loaded path

[sameera]

As a Nexus maintainer, I want the authored components to live where the harness never loads them, so that there is exactly one copy that can run and I always know which one it is.

Acceptance Criteria

• Given this story is started, when the preceding story's issue is read, then it is closed and carries the recorded evidence that the checkout-pointing loop works on this machine.
• Given this story is started, when Make the Python toolkit reachable by name and let it find the executable by name #249's story for the runtime resolver lookups is read, then it is closed — because this story deletes the file those three sites read.
• Given the Nexus repository after this story, when its .claude/ directory is listed, then it carries no Nexus-namespaced component file.
• Given a component placed only at the authored tree's new location and the install location not pointed at it, when the harness is started and asked for that component, then it is not offered — the location is not one the harness loads.
• Given a maintainer edits a component in the new location and invokes it, when the command runs, then the edited body is what runs.
• Given the repository's own user-owned files under .claude/, when the move completes, then they are untouched.
• Given the repository after this story, when the duplicate check runs on the maintainer's account, then it reports no duplicate.

Notes

This is the story that makes the adopter path honest: after it, the Nexus repository runs the same path an adopter runs, which is the only way that path stays exercised.

The alternative — exempt this repository, keep the tree at .claude/, and link the install location into the checkout so the loader deduplicates the two paths — is coherent and costs less. It was refuted because it makes the one-set invariant depend on undocumented deduplication behaviour, because it leaves component files at a loaded path in the repository whose maintainer most needs to know which copy is running, and because the exemption becomes a second rule the duplicate check must carry forever.