v1.13.0

### Added

* [#5139](https://github.com/firecracker-microvm/firecracker/pull/5139): Added support for [PVTime](https://docs.kernel.org/virt/kvm/arm/pvtime.html). This is used to support steal time on ARM machines.
* [#5175](https://github.com/firecracker-microvm/firecracker/pull/5175): Allow including a custom cpu template directly in the json configuration file passed to `--config-file` under the `cpu_config` key.
* [#5274](https://github.com/firecracker-microvm/firecracker/pull/5274): Allow taking diff snapshots even if dirty page tracking is disabled, by using `mincore(2)` to overapproximate the set of dirty pages. Only works if swap is disabled.
* [#5290](https://github.com/firecracker-microvm/firecracker/pull/5290): Extended MMDS to support the EC2 IMDS-compatible session token headers (i.e. "X-aws-ec2-metadata-token" and "X-aws-ec2-metadata-token-ttl-seconds") alongside the MMDS-specific ones.
* [#5290](https://github.com/firecracker-microvm/firecracker/pull/5290): Added `mmds.rx_invalid_token` and `mmds.rx_no_token` metrics to track the number of GET requests that were rejected due to token validation failures in MMDS version 2. These metrics also count requests that would be rejected in MMDS version 2 when MMDS version 1 is configured. They helps users assess readiness for migrating to MMDS version 2.
* [#5310](https://github.com/firecracker-microvm/firecracker/pull/5310): Added an optional `imds_compat` field (default to false if not provided) to PUT requests to `/mmds/config` to enforce MMDS to always respond plain text contents in the IMDS format regardless of the `Accept` header in requests. Users need to regenerate snapshots.
* [#5364](https://github.com/firecracker-microvm/firecracker/pull/5364): Added PCI support in Firecracker. PCI support is optional. Users can enable it passing the `--enable-pci` flag when launching the Firecracker process. When Firecracker process is launched with PCI support, it will create all VirtIO devices using a PCI VirtIO transport. If not enabled, Firecracker will use the MMIO transport instead.

### Changed

* [#5165](https://github.com/firecracker-microvm/firecracker/pull/5165): Changed Firecracker snapshot feature from developer preview to generally available. Incremental snapshots remain in developer preview.
* [#5282](https://github.com/firecracker-microvm/firecracker/pull/5282): Updated jailer to no longer require the executable file name to contain `firecracker`.
* [#5290](https://github.com/firecracker-microvm/firecracker/pull/5290): Changed MMDS to validate the value of "X-metadata-token-ttl-seconds" header only if it is a PUT request to /latest/api/token, as in EC2 IMDS.
* [#5290](https://github.com/firecracker-microvm/firecracker/pull/5290): Changed MMDS version 1 to support the session oriented method as in version 2, allowing easier migration to version 2. Note that MMDS version 1 accepts a GET request even with no token or an invalid token so that existing workloads continue to work.

###  Deprecated

* [#5274](https://github.com/firecracker-microvm/firecracker/pull/5274): Deprecated the `enable_diff_snapshots` parameter of the `/snapshot/load` API. Use `track_dirty_pages` instead.

### Removed

* [#5411](https://github.com/firecracker-microvm/firecracker/pull/5411): Removed official support for Intel Skylake instances. Firecracker will continue to work on those instances, but we will no longer perform automated testing on them.

###  Fixed

* [#5222](https://github.com/firecracker-microvm/firecracker/pull/5222): Fixed network and rng devices locking up on hosts with non 4K pages.
* [#5226](https://github.com/firecracker-microvm/firecracker/pull/5226): Fixed MMDS to set `Content-Type` header correctly (i.e. `Content-Type: text/plain` for IMDS-formatted or error responses and `Content-Type: application/json` for JSON-formatted responses).
* [#5260](https://github.com/firecracker-microvm/firecracker/pull/5260): Fixed a bug allowing the block device to starve all other devices when backed by a sufficiently slow drive.
* [#4207](https://github.com/firecracker-microvm/firecracker/issues/4207): Fixed GSI numbering on aarch64 to correctly allow up to 96 devices being attached simultaneously.
* [#5290](https://github.com/firecracker-microvm/firecracker/pull/5290): Fixed MMDS to reject PUT requests containing `X-Forwarded-For` header regardless of its casing (e.g. `x-forwarded-for`).
* [#5328](https://github.com/firecracker-microvm/firecracker/pull/5328): Fixed MMDS to set the token TTL header (i.e. "X-metadata-token-ttl-seconds" or "X-aws-ec2-metadata-token-ttl-seconds") in the response to "PUT /latest/api/token", as EC2 IMDS does.