Build project home and community pages

[diegosilval]

Implements Website Phase 2 for Eclipse Coffee Builder.

Changes include:

• build the public project Home page
• explain the archetype and Maven plugin workflow
• present the five Coffee Builder design principles
• add project development and incubation status
• add the Community and Contributing page
• link official Eclipse project, source, issues, mailing list, security, and legal resources
• strengthen validation against obsolete branding, analytics, coordinates, and release claims
• preserve Hugo safe rendering by keeping presentation markup in layouts

Validation:

• Hugo 0.144.2 Extended production build succeeds with --panicOnWarning
• root and subpath builds succeed
• all expected routes return HTTP 200
• Home calls to action resolve
• Community links validated
• prohibited-content scans pass
• UTF-8 validation passes
• visual inspection completed locally

No deployment or release configuration is included.