Document aspire do pipelines and migration from publishing callbacks (#436)

* Initial plan

* Add comprehensive aspire do pipelines documentation

Co-authored-by: IEvangelist <7679720+IEvangelist@users.noreply.github.com>

* Fix code block title format and revert unrelated file changes

Co-authored-by: IEvangelist <7679720+IEvangelist@users.noreply.github.com>

* Use Aspire CLI title format and fix consistency issues

Co-authored-by: IEvangelist <7679720+IEvangelist@users.noreply.github.com>

* Fix inaccurate diagnostics output example and remove unverified WithPipelineConfiguration API usage

Co-authored-by: IEvangelist <7679720+IEvangelist@users.noreply.github.com>

* Apply editorial suggestions from alistairmatthews review

Co-authored-by: alistairmatthews <41286777+alistairmatthews@users.noreply.github.com>

* fix: update trivy-action from 0.24.0 to v0.35.0 (old tag removed after supply chain attack)

Co-authored-by: alistairmatthews <41286777+alistairmatthews@users.noreply.github.com>
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Co-authored-by: IEvangelist <7679720+IEvangelist@users.noreply.github.com>
Co-authored-by: alistairmatthews <41286777+alistairmatthews@users.noreply.github.com>
Co-authored-by: AJ Matthews <alistair.matthews@civica.co.uk>

Author: 3 people