feat: player embed code generator

[omgate234]

Pull Request

Description:
Add get_embed_code() API across SDK objects to generate iframe embed HTML from player_url values, enabling users to easily share embeddable video players.

Changes:

• Add player_url_to_embed_url() utility to convert /watch?v= URLs to /embed?v= URLs
• Add build_iframe_embed_code() utility to generate iframe HTML strings
• Add get_embed_code() method to Video, Shot, SearchResult
• Add get_embed_code() method to timeline.Timeline, editor.Timeline
• Add get_embed_code() method to RTStreamShot, RTStreamExportResult, RTStream
• Export build_iframe_embed_code from videodb for use with raw dict responses
• Fix Video.generate_stream() to save player_url to instance (consistency with other classes)

Related Issues:

• N/A

Testing:

• Unit tests added in tests/test_embed_code.py covering:
  • player_url_to_embed_url() URL conversion and error cases
  • build_iframe_embed_code() iframe generation with various parameters
  • get_embed_code() method behavior on SDK objects
  • Error handling when player_url is unavailable

Usage Examples:

# Video
video = coll.get_video("...")
embed = video.get_embed_code()

# Search result with custom params
search_result = coll.search("launch announcement")
embed = search_result.get_embed_code(height=480, title="Search Highlights")

# For raw dict responses (CaptureSession.export)
from videodb import build_iframe_embed_code
resp = capture_session.export()
embed = build_iframe_embed_code(resp["player_url"])

[ankit-v2-3]

Looks good to me

[omgate234]

Looks good to me

Let me test more rigorously before we merge