feat: Add blog post on Feast dbt integration (#5915)

* Initial plan

* Add comprehensive blog post on Feast dbt integration

Co-authored-by: franciscojavierarceo <4163062+franciscojavierarceo@users.noreply.github.com>

* Apply suggestion from @franciscojavierarceo

* Reframe blog post from dbt user perspective

Co-authored-by: franciscojavierarceo <4163062+franciscojavierarceo@users.noreply.github.com>

* Fix SQL comment syntax and improve quotation consistency

Co-authored-by: franciscojavierarceo <4163062+franciscojavierarceo@users.noreply.github.com>

* Replace ML/machine learning with AI throughout blog post

Co-authored-by: franciscojavierarceo <4163062+franciscojavierarceo@users.noreply.github.com>

* Fix incorrect CLI flags and outdated references in dbt blog post

- Use -m/--manifest-path flag instead of positional args (9 instances)
- Replace --tag-filter with correct --tag flag (3 instances)
- Remove non-existent --no-online flag
- Fix CI/CD example: -t feast set timestamp-field, use --tag feast
- Update feast dbt list output to match actual CLI format
- Bump GitHub Actions versions from v2 to v4/v5
- Update Python version from 3.9 to 3.11

Signed-off-by: yassinnouh21 <yassinnouh21@gmail.com>

* Add files via upload

* Update hero image to use dbt+feast.png

Co-authored-by: franciscojavierarceo <4163062+franciscojavierarceo@users.noreply.github.com>

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Signed-off-by: yassinnouh21 <yassinnouh21@gmail.com>
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: franciscojavierarceo <4163062+franciscojavierarceo@users.noreply.github.com>
Co-authored-by: Francisco Javier Arceo <arceofrancisco@gmail.com>
Co-authored-by: yassinnouh21 <yassinnouh21@gmail.com>
Co-authored-by: Francisco Javier Arceo <farceo@redhat.com>

Author: 3 people