feat: add pi hook installer (#3398)

Support installing the pi extension via `atuin hook install pi`. Bundle
the extension in the binary and update the docs.

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## Checks
- [ ] I am happy for maintainers to push small adjustments to this PR,
to speed up the review cycle
- [ ] I have checked that there are no existing pull requests for the
same thing

1 files changed, 19 insertions, 3 deletions

diff --git a/crates/atuin-client/src/history.rs b/crates/atuin-client/src/history.rs
index 996208d9..16f7d85a 100644
--- a/crates/atuin-client/src/history.rs
+++ b/crates/atuin-client/src/history.rs
@@ -19,7 +19,7 @@ mod builder;
 pub mod store;
 
 /// Known AI agent author values. Used to expand `$all-agent` and `$all-user` filters.
-pub const KNOWN_AGENTS: &[&str] = &["claude-code", "codex", "copilot"];
+pub const KNOWN_AGENTS: &[&str] = &["claude-code", "codex", "copilot", "pi"];
 pub const AUTHOR_FILTER_ALL_USER: &str = "$all-user";
 pub const AUTHOR_FILTER_ALL_AGENT: &str = "$all-agent";
 
@@ -540,9 +540,12 @@ mod tests {
     use regex::RegexSet;
     use time::macros::datetime;
 
-    use crate::{history::HISTORY_VERSION, settings::Settings};
+    use crate::{
+        history::{AUTHOR_FILTER_ALL_AGENT, AUTHOR_FILTER_ALL_USER, HISTORY_VERSION},
+        settings::Settings,
+    };
 
-    use super::History;
+    use super::{History, author_matches_filters, is_known_agent};
 
     // Test that we don't save history where necessary
     #[test]
@@ -604,6 +607,19 @@ mod tests {
     }
 
     #[test]
+    fn known_agents_include_pi() {
+        assert!(is_known_agent("pi"));
+        assert!(author_matches_filters(
+            "pi",
+            &[AUTHOR_FILTER_ALL_AGENT.to_string()]
+        ));
+        assert!(!author_matches_filters(
+            "pi",
+            &[AUTHOR_FILTER_ALL_USER.to_string()]
+        ));
+    }
+
+    #[test]
     fn disable_secrets() {
         let settings = Settings {
             secrets_filter: false,