chore(deps): update dependency element-hq/synapse to v1.148.0 (#4203)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [element-hq/synapse](https://github.com/element-hq/synapse) | minor | `v1.147.1` → `v1.148.0` |

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### Release Notes

<details>
<summary>element-hq/synapse (element-hq/synapse)</summary>

### [`v1.148.0`](https://github.com/element-hq/synapse/releases/tag/v1.148.0)

[Compare Source](https://github.com/element-hq/synapse/compare/v1.147.1...v1.148.0)

### Synapse 1.148.0 (2026-02-24)

No significant changes since 1.148.0rc1.

### Synapse 1.148.0rc1 (2026-02-17)

#### Features

- Support sending and receiving [MSC4354 Sticky Event](https://github.com/matrix-org/matrix-spec-proposals/pull/4354) metadata. ([#&#8203;19365](https://github.com/element-hq/synapse/issues/19365))

#### Improved Documentation

- Fix reference to the `experimental_features` section of the configuration manual documentation. ([#&#8203;19435](https://github.com/element-hq/synapse/issues/19435))

#### Deprecations and Removals

- Remove support for [MSC3244: Room version capabilities](https://github.com/matrix-org/matrix-spec-proposals/pull/3244) as the MSC was rejected. ([#&#8203;19429](https://github.com/element-hq/synapse/issues/19429))

#### Internal Changes

- Add in-repo Complement tests so we can test Synapse specific behavior at an end-to-end level. ([#&#8203;19406](https://github.com/element-hq/synapse/issues/19406))
- Push Synapse docker images to Element OCI Registry. ([#&#8203;19420](https://github.com/element-hq/synapse/issues/19420))
- Allow configuring the Rust HTTP client to use HTTP/2 only. ([#&#8203;19457](https://github.com/element-hq/synapse/issues/19457))
- Correctly refuse to start if the Rust workspace config has changed and the Rust library has not been rebuilt. ([#&#8203;19470](https://github.com/element-hq/synapse/issues/19470))

</details>

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---

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Reviewed-on: https://gitea.alexlebens.dev/alexlebens/infrastructure/pulls/4203
Co-authored-by: Renovate Bot <renovate-bot@alexlebens.net>
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clusters/cl01tl/helm/matrix-synapse/Chart.yaml

@@ -81,4 +81,4 @@ dependencies:
     repository: oci://harbor.alexlebens.net/helm-charts
 icon: https://cdn.jsdelivr.net/gh/selfhst/icons/png/matrix.png
 # renovate: datasource=github-releases depName=element-hq/synapse
-appVersion: v1.147.1
+appVersion: v1.148.0