Update workspace manifest remotes for Base Foundry

[codeforester]

Context

base-workspace moved to basefoundry/base-workspace, and the workspace manifest still points moved Base-family repositories at codeforester. Some personal/private repos intentionally remain under codeforester.

Scope

• Update workspace.yaml remotes for moved repositories: base, base-workspace, banyanlabs, base-demo, and base-platform-tools to basefoundry URLs.
• Keep personal repos such as bankbuddy, brew, and blend under codeforester unless they are moved separately.
• Update README links to Base from github.com/codeforester/base to github.com/basefoundry/base.
• Verify SSH versus HTTPS remote styles remain intentional for each workspace entry.

Validation

• rg -n "github.com:codeforester|github.com/codeforester" README.md workspace.yaml and review remaining hits as intentional personal repos.
• /Users/rameshhp/work/base/bin/basectl workspace status --manifest workspace.yaml
• git diff --check