fix(flake): Make the flake actually run

[RasmusRendal]

In order to make the Nix flake work for Synapse development:

• Bump flake.lock
• Bump devenv
• Bump Rust to 1.89
• Bump Perl

I also removed the built-in prompt. I have my own prompt, which I much prefer.

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Note

Low Risk
Changes affect only local Nix/devenv development setup, not production Synapse runtime or application code.

Overview
Updates the Synapse Nix flake so nix develop / devenv up work again with current tooling.

devenv is bumped from v0.6.3 to v2.0.6, with a full flake.lock refresh (nixpkgs, rust-overlay, crate2nix, git-hooks, and related inputs). Synapse startup hooks now use process.manager.before instead of process.before, matching devenv 2’s process manager API.

The dev shell pins Rust stable 1.89.0 (was 1.82.0) and switches SyTest’s Perl module path from perl538Packages to perl5Packages. Built-in Starship prompt integration is removed (starship.enable deleted).

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 80.86%. Comparing base (570ad41) to head (ee3f538).

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #252      +/-   ##
==========================================
- Coverage   80.87%   80.86%   -0.01%     
==========================================
  Files         504      504              
  Lines       72717    72717              
  Branches    10973    10973              
==========================================
- Hits        58807    58806       -1     
- Misses      10621    10622       +1     
  Partials     3289     3289              

see 1 file with indirect coverage changes

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[cursor]

Cursor Bugbot has reviewed your changes using high effort and found 1 potential issue.

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[cursor]

Before hook skipped by native manager

High Severity

Issue: process.manager.before does not run under devenv 2.0.6's default native process manager, so devenv up skips homeserver config generation and Synapse cannot start.

Fix: Use a devenv task that runs before processes, or set process.manager.implementation = "process-compose".

 

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