Enable persistent sessions - #394

* start persistent session work

* add streaming option to API

* basic streaming working

* sessionmanager

* non-streaming works

* cli chat is working

* remove websocket client; add handle session endpoints

* e2e test compile

* skip saving streaming messages

* oops

* add endpoints for the sessions

* add release for agent charts

* combine stream logic

* add non-interactive CLI commands

* invoke with/without session works properly

* added bug_report and version

* wip

Signed-off-by: Peter Jausovec <[email protected]>

* switch UI chat to new streaming endpoint

Signed-off-by: Peter Jausovec <[email protected]>

* update tests + fix ruff warning

Signed-off-by: Peter Jausovec <[email protected]>

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Signed-off-by: Peter Jausovec <[email protected]>
Co-authored-by: Peter Jausovec <[email protected]>

Builds on kagent-dev#3395, now merged; rebased onto main.

Recover crashed runtimes during A2A sends when
`config.sessions.automaticRecovery: true`. The setting defaults to
`false`. The chart only mentions it in a comment, so a default install
renders the same `controller.yaml` as before and a rollback to v1.0.0
can still read it.

The flag controls joining an admitted recovery, recovering a send
refused for an open turn, recovering a send blocked by a suspension
whose worker was lost (the Actor crashed during the post-turn suspend),
and reverting after a proven unaccepted send. A send waits at most 10
seconds for recovery; a recovery still running is answered
`KAGENT_SEND_NOT_ACCEPTED` with `state: RECOVERING`, and the client's
retry continues it. If recovery can't run, the send keeps the answer it
gives without recovery. With the flag off, sends keep their existing
refusals. Explicit `RevertSession` calls remain available.

Missing or replaced runtimes are recorded as FAILED/NONE with reason
`RuntimeLost`. These persistence changes apply with either flag value.
The flag does not control migrations, schema, or stored data.

Chat reads recovery status from stored Session state. It retries
`KAGENT_SEND_NOT_ACCEPTED` before the first stream frame, with the same
message ID. The wait doubles from `retryAfterMs` up to 2 seconds, within
a 30-second window. Chat offers Recover, which calls `RevertSession`, in
three cases: when the window runs out; when a send is refused for an
open turn (`KAGENT_TURN_ACTIVE`), which is what a mid-turn crash
produces with the flag off while the Session still reads READY; and
while a recovery is pending. A recovery whose attempt failed stays
FAILED/REVERT until a client retries it. Recover returns a healthy
runtime unchanged and records a lost one. Session reads do not query
Substrate.

Validation:

- Gateway tests cover all three disabled paths and the existing enabled
paths.
- Config tests cover the default, both values, Helm rendering, and the
deployment checksum. A helm-unittest asserts the default render omits
the flag.
- PostgreSQL-backed Session, database, gRPC, and scheduled-run
controller tests pass.
- UI tests cover the backoff, both refusal tags, and every Recover path,
including a revert that records a lost runtime.
- Vitest workers are capped at eight (`min(cores - 1, 8)`); the default
oversubscribed large machines and made heavy page tests time out. Three
consecutive full runs pass, 846/846.
- On kind, flag off: deleting the worker mid-turn reproduces kagent-dev#394. The
refused send offers Recover, Recover restores the runtime, and the next
message is answered. Recover during a healthy running turn leaves it
running. Screenshots and logs: [evidence
gist](https://gist.github.com/adalundhe/533ce0841c58cdea0018bcc62058dccb).
- On kind, flag on: a worker deleted while the Actor suspends after a
turn leaves the Session stuck before this change, and the next send
recovers it after. Logs: [suspension-crash
gist](https://gist.github.com/adalundhe/426f7e31388b2a59df517572788e9e2c).
- Protobuf, Go and UI lint pass. Live crash-recovery E2E explicitly
enables the flag in CI.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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Signed-off-by: Ada Lundhe <[email protected]>
Co-authored-by: Claude Opus 5.5 <[email protected]>