feat: Add history author/intent metadata and v1 record version (#3205)

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Adds `author` and `intent` to client history records and DB persistence,
including migration/backfill and CLI/daemon propagation.
Introduces V2 record-store history version `v1` while retaining read
compatibility for legacy `v0` records.
Adds `--author` and `--intent` flags to `atuin history start`, plus
`{author}` and `{intent}` format keys for listing/history output.
Updates shell-integration docs for `ATUIN_HISTORY_AUTHOR` and
`ATUIN_HISTORY_INTENT`, and updates related tests/fixtures.
Validated with `cargo test -p atuin-client --lib`, `cargo test -p
atuin-daemon --tests`, `cargo test -p atuin search::inspector`, and
`cargo fmt --check`.

0 files changed, 0 insertions, 0 deletions