* docs: Add course content for Day 0
* added static
* added videos and removed video template files
* wording
* added youtube links
* added deliverable
* checked code
* added images
* added image links
* fixed image
* linebreak under video
* started working on day 1
* updated pitstop structure
* pitstop Reflect on Your Findings
* pitstop fix
* removed filtering from build-simple-vector-search and used create_payload_index instead of unindexed_filtering_retrieve in pitstop
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Co-authored-by: Kirstin <kirstin.taufertshoefer@qdrant.com>