[BUG]: Navbar top-right controls (network selector + connected-address chip) need a standard button treatment

Bug Description

Issue Description

In components/layout/Navbar.tsx, the top-right controls next to the theme toggle — the network selector ({network} ▾ with the green status dot, lines ~66–94) and the connected wallet address chip (<NavbarButton>{address}</NavbarButton>, lines ~96–102) — don't read as proper buttons. They're small, inconsistently sized/padded compared to Connect Wallet, have no visible hover/focus state, and the network dropdown trigger looks like plain text with a caret rather than a control.

Steps to Reproduce

1. Open any page, connect a wallet (or just view the disconnected Connect Wallet state for comparison).
2. Look at the top-right of the navbar: theme toggle, network pill, address pill.
3. Compare their height/padding/radius against Connect Wallet and against each other.

Expected

All top-right controls (theme toggle, network selector, address chip, Connect Wallet) share one consistent button language: same height, consistent horizontal padding, matching corner radius, visible hover state, and a keyboard focus-visible ring — so the cluster reads as one coherent group instead of mismatched pieces.

Scope

• Restyle the network-selector trigger and the connected-address NavbarButton (and its mobile counterparts around lines ~171–195) to a consistent pill/button style: fixed height matching Connect Wallet, consistent px/py, matching rounded-full, clear :hover and :focus-visible states.
• Keep the network dropdown menu contents, the list of networks, and the disconnect behavior unchanged — restyle triggers only.
• Keep the live-status dot on the network pill, just align it with the new sizing.
• Light + dark mode.
• Do not change useWallet() logic, switchNetwork, or disconnectWallet behavior.

Acceptance Criteria

• Network selector, address chip, and Connect Wallet share consistent height/padding/radius.
• Both pills have visible :hover and :focus-visible states.
• Network dropdown still opens/closes and switches networks correctly.
• Wallet disconnect still works from both desktop and mobile menus.
• Light + dark mode verified.
• npm run lint passes.
• npx tsc --noEmit passes.
• npm run build passes.
• Before/after screenshots (connected + disconnected, light + dark).
• No change to wallet/network logic — visual only.

AI-assisted contributions are allowed; disclose AI usage in the PR and do not AI-generate the entire component.

Steps to Reproduce

No response

Logs and Screenshots

No response

Environment Details

No response

Impact

Critical - Application is unusable

Code of Conduct

• I have joined the Discord server and will post updates there
• I have searched existing issues to avoid duplicates