) (#27138)

Backport of #27128

Original PR: #27128 — docs(docs/install/releases): update release
calendar for v2.35.1
Merge commit: 20ee006
Requested by: @nickvigilante

Co-authored-by: Denis Afonso <denisra@users.noreply.github.com>

Cherry-pick of #27132 (`f84801ee`) onto `release/2.35`.

gpt-5.6 models were unusable with agents: fantasy's Responses allowlist
did not include the new family, so `IsResponsesModel` returned false and
chatd fell back to the Chat Completions path (no reasoning params, no
encrypted reasoning continuity).

## Changes

- Bump the `charm.land/fantasy` replace pin from `2e3ddbca75dd` to
coder/fantasy `6da0c3b10237` (coder_2_33), pulling in:
- coder/fantasy#46: route `gpt-5.6-sol`, `gpt-5.6-terra`, `gpt-5.6-luna`
through the OpenAI Responses API as reasoning models.
- coder/fantasy#41: surface Anthropic refusal stop_reason as
content-filter (rides along; sits below #46 on coder_2_33).
- Update the fork changelog comment in go.mod.

## Backport safety

- The delta over 2.35's pin is exactly the two commits above; #27132
itself touched only go.mod/go.sum, and no coder/coder code references
the refusal metadata or content-filter finish reason (verified on main
and 2.35).
- Finish-part provider metadata is never persisted by chatd, so a
rollback to an unpatched 2.35.x binary cannot hit undecodable stored
history.
- `go build ./coderd/...` and `go test
./coderd/x/chatd/{chatopenai,chatprovider,chatprompt,chatloop}/` pass on
this branch; `go mod tidy` is a no-op.

> This PR was authored by Mux on Mike's behalf.

…27137)

Cherry-pick of #26822 (`f77d0065ed`) onto `release/2.35`.

The gvisor `replace` directive on this branch targets `gvisor.dev`
instead of the module path `gvisor.dev/gvisor`. Go matches replace
directives by exact module path, so the directive is a silent no-op:
v2.34.5, v2.35.0, and v2.35.1 all built against upstream gvisor
`v0.0.0-20240509041132` without the integer-overflow crash fix from
coder/gvisor (#20885). `go.sum` on this branch has no `coder/gvisor`
entries, confirming the fork was not in the build.

## Changes

- Correct the replace directive to `gvisor.dev/gvisor =>
github.com/coder/gvisor v0.0.0-20260313164934-7a658db7b714` (go.mod +
go.sum).

## Verification

- `go list -m gvisor.dev/gvisor` now resolves to
`github.com/coder/gvisor v0.0.0-20260313164934-7a658db7b714`.
- `go mod tidy` is a no-op; `go build ./agent/... ./tailnet/...` passes.
- main and `release/2.34` already carry this fix; `release/2.35` was the
only maintained branch missing it.

> This PR was authored by Mux on Mike's behalf.

…#27083) (#27142)

Backport of #27083

Original PR: #27083 — fix(site): keep activity bump editable when
allow_user_autostop is on
Merge commit: 1eea4a7
Requested by: @rowansmithau

Co-authored-by: Jake Howell <jacob@coder.com>