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`.

1 files changed, 2 insertions, 0 deletions

diff --git a/crates/atuin-daemon/proto/history.proto b/crates/atuin-daemon/proto/history.proto
index 9fbd3372..2a45b7cf 100644
--- a/crates/atuin-daemon/proto/history.proto
+++ b/crates/atuin-daemon/proto/history.proto
@@ -8,6 +8,8 @@ message StartHistoryRequest {
   string cwd = 3;
   string session = 4;
   string hostname = 5;
+  string author = 6;
+  string intent = 7;
 }
 
 message EndHistoryRequest {