…rements for Onion and I2P nodes

b061b35 seeds: Regenerate mainnet seeds (virtu)
02dc45c seeds: Pull nodes from Luke's seeder (virtu)
7a2068a seeds: Pull nodes from virtu's crawler (virtu)

Pull request description:

  This builds on #30008 and adds data [exported](https://github.com/virtu/seed-exporter) by [my crawler](https://github.com/virtu/p2p-crawler) an additional source for seed nodes. Data covers all supported network types.

  [edit: Added Luke's seeder as input as well.]

  ### Motivation
  - Further decentralizes the seed node selection process (in the long term potentially enabling an _n_-source threshold for nodes to prevent a single source from entering malicious nodes)
  - No longer need to manually curate seed node list for any network type: See last paragraph of OP in #30008. My crawler has been [discovering the handful of available cjdns nodes](https://21.ninja/reachable-nodes/nodes-by-net-type/) for around two months, all but one of which meet the reliability criteria.
  - Alignment of uptime requirements for Onion and I2P nodes with those of clearnet nodes to 50%: If I'm reading the code correctly, seeders appear to optimize for up-to-dateness by using [lower connection timeouts](https://github.com/achow101/dnsseedrs/blob/3c1a63c6723819871d76fe0fbd2155fe5a5bb171/src/crawl.rs#L349) than [Bitcoin Core](https://github.com/bitcoin/bitcoin/blob/bc87ad98543299e1990ee1994d0653df3ac70093/src/netbase.cpp#L40C27-L40C48) to maximize throughput. Since my crawler does not have the same timeliness requirements, it opts for accuracy by using generous timeouts. As a result, its data contains additional eligible Onion (and other darknet nodes), as is shown in the histogram below. Around 4500 Onion nodes are discovered so far (blue); my data adds ~6400 more (orange); ~ 1500 nodes take longer than the default 20-second Bitcoin Core timeout and won't qualify as "good".

  ![Connection time histogram for Onion nodes](https://github.com/user-attachments/assets/c3513604-aa48-4c75-b51d-13421eaed9eb)

  Here's the current results with 512 nodes for all networks except cjdns:
  <details>
  <summary>Using the extra data</summary>

  ```
  IPv4   IPv6  Onion  I2P    CJDNS Pass
  10335   2531  11545   1589     10 Initial
  10335   2531  11545   1589     10 Skip entries with invalid address
  5639   1431  11163   1589      8 After removing duplicates
  5606   1417  11163   1589      8 Enforce minimal number of blocks
  5606   1417  11163   1589      8 Require service bit 1
  4873   1228  11163   1589      8 Require minimum uptime
  4846   1225  11161   1588      8 Require a known and recent user agent
  4846   1225  11161   1588      8 Filter out hosts with multiple bitcoin ports
  512    512    512    512      8 Look up ASNs and limit results per ASN and per net
  ```
  </details>
  <details>
  <summary>Before</summary>

  ```
  IPv4   IPv6  Onion  I2P    CJDNS Pass
  5772   1323    443      0      2 Initial
  5772   1323    443      0      2 Skip entries with invalid address
  4758   1110    443      0      2 After removing duplicates
  4723   1094    443      0      2 Enforce minimal number of blocks
  4723   1094    443      0      2 Require service bit 1
  3732    867    443      0      2 Require minimum uptime
  3718    864    443      0      2 Require a known and recent user agent
  3718    864    443      0      2 Filter out hosts with multiple bitcoin ports
   512    409    443      0      2 Look up ASNs and limit results per ASN and per net
  ```
  </details>

  ### To dos
  - [x] Remove manual nodes and update README
  - [x] Mark nodes with connection times exceeding Bitcoin Core's default as bad in [exporter](https://github.com/virtu/seed-exporter): [done](virtu/seed-exporter#12)
  - [x] Regenerate mainnet seeds
  - [x] Rebase, then remove WIP label once #30008 gets merged

ACKs for top commit:
  achow101:
    ACK b061b35
  fjahr:
    utACK b061b35

Tree-SHA512: 63e86220787251c7e8d2d5957bad69352e19ae17d7b9b2d27d8acddfec5bdafe588edb68d77d19c57f25f149de723e2eeadded0c8cf13eaca22dc33bd8cf92a0