isisd: When the metric-type is configured as "wide", the IS-IS generates incorrect metric values for IPv4 directly connected routes.
The IPv4 directly connected route prefix exists in both the root LSP and the root's neighbor LSP:
1. When generating vertices for directly connected route prefixes with a metric of 0 based on the root LSP, the isis_spf_preload_tent_ip_reach_cb function only generates vertices of type VTYPE_IPREACH_INTERNAL without distinguishing between area->oldmetric and area->newmetric.
2. When generating vertices for the directly connected route prefix based on the neighbor LSP, the isis_spf_process_lsp function will generate vertices of type VTYPE_IPREACH_INTERNAL and VTYPE_IPREACH_TE based on area->oldmetric and area->newmetric, where the vertex metric is the sum of the metric from the root IS to the neighbor IS and from the neighbor IS to the root IS, respectively.
If area->newmetric=1, the same directly connected route prefix will have both VTYPE_IPREACH_INTERNAL vertices with a metric of 0 and VTYPE_IPREACH_TE vertices with a non-zero metric. During route generation, the isis_spf_loop function will prioritize selecting VTYPE_IPREACH_TE vertices, leading to incorrect metrics for the directly connected routes.
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