Fix README Files (#70)

* docs: sync README files with Documentation.docc for v2.0.0 APIs

Updated all README files to align with v2.0.0 APIs documented in .docc files:

Main README.md:
- Update installation to reference separate plugin repositories
- Update WatchConnectivity examples to v2.0.0 APIs
- Update Messagable protocol signature (throwing init, Sendable)
- Update ConnectivityObserver with MessageDecoder integration
- Clarify plugin distribution strategy

SundialKitStream README.md:
- Create comprehensive standalone documentation
- Add network monitoring with @observable and AsyncStream
- Add WatchConnectivity with actor-based observers
- Add type-safe messaging examples
- Add architecture overview and comparison table

SundialKitCombine README.md:
- Create comprehensive standalone documentation
- Add network monitoring with @published and Combine
- Add WatchConnectivity with @mainactor observers
- Add advanced reactive patterns
- Add architecture overview and comparison table

All examples now use v2.0.0 APIs consistently with separate repository
installation for plugins.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

* docs: standardize logo to .docc Resources and remove Assets directory

Standardized all documentation to use logo.png from .docc Resources:
- Main README uses Sources/SundialKitNetwork/.../logo.png
- Plugin READMEs use their own local .docc Resources/logo.png
- Updated SundialKit.docc from logo.jpg to logo.png

Removed Assets directory:
- Deleted Assets/logo.svg (replaced with .docc logo.png)
- Deleted Assets/Readme-Sundial.gif (removed from README)
- Deleted Assets/Reachable-Sundial.gif (removed from README)
- Deleted unused .mov files

All logos now sourced from .docc Resources for consistency across
documentation and subrepos.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

* docs: add TOC to all READMEs and streamline main README for SundialKitStream

- Add Table of Contents to SundialKitStream and SundialKitCombine READMEs
- Simplify main README installation section to focus on SundialKitStream
- Remove "Option A/B" structure from main README usage section
- Add clear links to SundialKitCombine for users needing Combine support
- Present SundialKitStream as the recommended modern approach

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

* docs: replace WatchConnectivity examples with SundialKitStream

- Replace Connection Status example to use AsyncStream instead of Combine
- Replace Sending and Receiving Messages example with SundialKitStream
- Replace Messagable protocol example with SundialKitStream
- Update model classes to use @observable and async/await patterns
- Remove all SundialKitCombine references from main usage examples

All WatchConnectivity examples now consistently use SundialKitStream
with modern async/await patterns throughout the main README.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

* docs: fix Messagable protocol requirements and NetworkPing example

- Correct Messagable protocol documentation: key is optional, not required
- Add clarification that type name is used as default key if not provided
- Update NetworkPing example to use @observable model instead of ObservableObject
- Remove @published pattern from NetworkPing example

All code examples now consistently use SundialKitStream patterns.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

* docs: fix plugin README TOC anchors and Contributing sections

- Fix broken TOC anchor links with spaces in package names
- Replace monorepo Contributing references with standalone guidelines
- Add comprehensive contributing instructions for both packages

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

* Fixing README content

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Co-authored-by: Claude <noreply@anthropic.com>

Author: leogdion