snapcraft.yaml: use core24 as build-base

[valentindavid]

Thanks for helping us make a better snapd! Have you signed the license agreement and read the contribution guide?

[valentindavid]

We might need to start publishing core24 fips.

[github-actions[bot]]

Tue Oct 21 16:47:47 UTC 2025 The following results are from: https://github.com/canonical/snapd/actions/runs/18688277291

Failures:

Preparing:

• openstack-ps7:ubuntu-core-18-64:tests/main/
• openstack-ps7:ubuntu-core-18-64:tests/core/
• openstack-ps7:ubuntu-24.04-64:tests/main/lxd-try

Executing:

• openstack-ps7:arch-linux-64:tests/main/snap-run-inhibition-flow
• openstack-ps7:debian-12-64:tests/unit/go:clang
• openstack-ps7:ubuntu-core-20-64:tests/core/snapd-failover
• openstack-ps7:ubuntu-core-24-64:tests/core/basic20plus
• openstack-ps7:ubuntu-core-24-64:tests/main/dbus-activation-system
• openstack-ps7:ubuntu-20.04-64:tests/main/snap-advise-command
• openstack-ps7:ubuntu-24.04-64:tests/unit/go:clang

Restoring:

• openstack-ps7:ubuntu-20.04-64:tests/main/interface-allow-auto-connection:true
• openstack-ps7:ubuntu-20.04-64:tests/main/interface-allow-auto-connection:false

[Meulengracht]

We might need to start publishing core24 fips.

let us sync with gabriel on this

[valentindavid]

What are the constraints when moving snapd to a newer build base? Can we just do it?

Just FIPS.

[codecov[bot]]

Codecov Report

:white_check_mark: All modified and coverable lines are covered by tests. :white_check_mark: Project coverage is 77.39%. Comparing base (a8af10d) to head (dd4344f).

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #14938      +/-   ##
==========================================
- Coverage   77.45%   77.39%   -0.07%     
==========================================
  Files        1321     1331      +10     
  Lines      180747   180895     +148     
  Branches     2385     2385              
==========================================
+ Hits       139991   139997       +6     
- Misses      32253    32389     +136     
- Partials     8503     8509       +6     

Flag	Coverage Δ
unittests	77.39% <ø> (-0.07%)	:arrow_down:

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