Summary

GetDoltServerHost() resolves the Dolt server host as
BEADS_DOLT_SERVER_HOST env > metadata.json dolt_server_host > 127.0.0.1
— skipping the ~/.config/bd/config.yaml / global config layer. This
makes the host story asymmetric with port: GH#2073 added config.yaml
consultation for dolt.port in DefaultConfig (commit e6734290),
but no analogous fix for host has landed.

Why this matters

Multi-developer teams sharing a single tailnet-reachable Dolt
sql-server want to pin the host once per user in
~/.config/bd/config.yaml. Without this, teams must either:

1. Set BEADS_DOLT_SERVER_HOST in every operator's shell profile
   (works but per-shell), or
2. Sweep per-clone .beads/metadata.json edits (works but per-repo).

Neither matches the documented "user config is consulted" precedence
that bd dolt show advertises.

We hit this on a factfiber.ai migration moving Dolt from per-dev
loopback to a shared tailnet IP. The port fix from GH#2073 helped;
host needed the symmetric treatment.

Patch

internal/configfile/configfile.go:

 // GetDoltServerHost returns the Dolt server host.
-// Checks BEADS_DOLT_SERVER_HOST env var first, then config, then default.
+// Priority: BEADS_DOLT_SERVER_HOST env var > metadata.json dolt_server_host
+// > config.yaml / global config dolt.host > DefaultDoltServerHost.
 func (c *Config) GetDoltServerHost() string {
     if h := os.Getenv("BEADS_DOLT_SERVER_HOST"); h != "" {
         return h
     }
     if c.DoltServerHost != "" {
         return c.DoltServerHost
     }
+    if h := config.GetYamlConfig("dolt.host"); h != "" {
+        return h
+    }
     return DefaultDoltServerHost
 }

Resulting precedence: env > metadata.json > config.yaml > default,
matching the order shown by bd dolt show and consistent with the
GH#2073 port fix.

Test plan

• New GetDoltServerHost_config_yaml subtest in
  internal/configfile/configfile_test.go covering four
  precedence branches: yaml-wins-when-metadata-empty,
  metadata-over-yaml, env-over-yaml, default-when-no-signal
  (existing default test continues to cover the last case).
• go test ./internal/configfile/ passes (with
  BEADS_DOLT_SERVER_HOST cleared from env — existing tests in
  TestDoltServerMode/GetDoltServerHost already assume this).
• gofmt clean, go vet clean.

Notes

• internal/configfile previously had no dependency on
  internal/config; the new import is one-directional, no cycle.
• Stale ~/.config/bd/config.yaml from prior bd dolt set host
  invocations could surprise users who expect the previous metadata-
  only behavior. Mitigation: bd doctor --fix or manual cleanup.
  This is the same surprise window the port fix introduced.