Base Services Hub contains external links without URL schemes

## Summary

The Base Services Hub page contains several external Markdown links without an explicit `https://` scheme. These may be interpreted as relative/internal links instead of external URLs.

## What I found

Examples in [docs/get-started/base-services-hub.mdx](cci:7://file:///C:/Users/Zeki/CascadeProjects/base-docs-research/docs/get-started/base-services-hub.mdx:0:0-0:0):

- `docs/get-started/base-services-hub.mdx:25` - `[Anchor Zero](anchorzero.com)`
- `docs/get-started/base-services-hub.mdx:27` - `[Artemis](artemis.xyz)`
- `docs/get-started/base-services-hub.mdx:30` - `[Chainalysis Hexagate](www.chainalysis.com)`
- `docs/get-started/base-services-hub.mdx:35` - `[Decubate Technologies](Decubate.com/tms)`
- `docs/get-started/base-services-hub.mdx:36` - `[Dune](www.dune.com/home)`
- `docs/get-started/base-services-hub.mdx:37` - `[Dynamic](Dynamic.xyz)`
- `docs/get-started/base-services-hub.mdx:38` - `[FailSafe](www.getfailsafe.com)`
- `docs/get-started/base-services-hub.mdx:43` - `[Galxe](www.galxe.com)`
- `docs/get-started/base-services-hub.mdx:44` - `[GetBlock](getblock.io)`
- `docs/get-started/base-services-hub.mdx:47` - `[Hexens](Hexens.io)`
- `docs/get-started/base-services-hub.mdx:50` - `[Layer3](layer3.xyz)`
- `docs/get-started/base-services-hub.mdx:51` - `[MCA - MultiChain Advisors Inc.](www.multichainadv.com)`
- `docs/get-started/base-services-hub.mdx:53` - `[Neynar](neynar.com)`
- `docs/get-started/base-services-hub.mdx:57` - `[OkHi](www.okhi.com)`
- `docs/get-started/base-services-hub.mdx:66` - `[Runtime Verification](runtimeverification.com)`
- `docs/get-started/base-services-hub.mdx:67` - `[Security.xyz](security.xyz)`
- `docs/get-started/base-services-hub.mdx:68` - `[Slash](slash.com)`
- `docs/get-started/base-services-hub.mdx:72` - `[Tunnl](tunnl.io)`

## Expected behavior

External company links should include a full URL scheme such as `https://`.

## Suggested fix

Update these links to include `https://`.

For example:

- `[Anchor Zero](https://anchorzero.com)`
- `[Artemis](https://artemis.xyz)`
- `[Chainalysis Hexagate](https://www.chainalysis.com)`

## Impact

The Services Hub is a directory page, so incorrect external links can prevent builders from reaching the listed services.